Code
B1351
ALFA ROMEO
B — Body
Ignition key-in-start switch short to positive
AI status
Completed
Completed
100%
Causes
- Chafed or damaged wiring harness with insulation worn to battery positive
- Corroded or loose connector at the ignition switch or BCM
- Faulty ignition key-in-start (ignition position) switch assembly
- Shorted splice or aftermarket accessory tied into the ignition feed
- Water ingress or contamination in switch/connector
- Intermittent BCM/control module hardware or ground fault
Symptoms
- Key position warnings or incorrect instrument cluster messages
- Starter engages unexpectedly or vehicle won’t crank when key turned
- Accessories powered when key is off, or inability to turn off accessories
- Possible fuse blow or repeated BCM faults
- Intermittent no-start or parasitic battery drain
What to check
- Scan vehicle and record freeze-frame data and related codes before clearing
- Visually inspect ignition switch connector, harness routing and nearby wiring for damage or aftermarket taps
- Check for corrosion, pushed pins, and proper connector mating at the switch and BCM
- Measure voltage at the ignition switch signal pin with key in OFF/ACC/ON/START positions
- Disconnect ignition switch connector and see if the fault clears or changes
- Perform wiggle test while monitoring the signal to reproduce the fault
Signal parameters
- Ignition signal open (expected): ~0–1 V (no key position contact)
- Ignition signal closed (ACC/ON/START): battery voltage ~11–14.5 V when switch contact is made
- Short-to-positive condition: signal measured at or near battery voltage in OFF position
- Intermittent short: fluctuating voltage between ~0 V and battery voltage during movement or vibration
Diagnostic algorithm
- Connect a scanner, read and record B1351 and any related codes and freeze-frame data.
- Inspect the ignition switch connector and harness for visible damage, corrosion or aftermarket splices.
- With ignition OFF, measure voltage at the ignition switch signal terminal. A steady battery voltage in OFF indicates a short to positive.
- Disconnect the ignition switch connector. If the code clears or the signal drops to ~0 V with the connector removed, suspect switch or harness between connector and BCM.
- If the signal remains high with the switch disconnected, trace and isolate the harness toward the BCM — look for a contact to battery feed or pinned terminal fault.
- Perform continuity and resistance checks between the ignition signal wire and battery positive, and between the signal wire and BCM pin using wiring diagrams. Repair any chafed wiring or shorted splices.
- Reconnect and operate the switch through all positions while monitoring voltage; replace the ignition switch assembly if internal contacts are faulty or stuck.
- After repairs, clear codes and retest for intermittent faults. If wiring and switch check good but code persists, consider BCM connector inspection and module diagnosis or replacement per manufacturer procedure.
- Safety note: Prevent unexpected starter engagement while testing. Follow OEM safety procedures when disconnecting electrical components or replacing modules.
Likely causes
- Ignition switch contact stuck or welded closed, holding the circuit at battery voltage
- Pin pushed out or terminal touching positive supply in connector
- Repair or accessory wiring incorrectly connected to ignition feed
- Damaged insulation where harness passes near battery/engine
- Corrosion inside connector making intermittent short to +B
Fault status
Status
B1351 — Ignition key-in-start switch circuit short to positive detected by BCM (ignition position signal held at battery voltage when it should be open).
Repair difficulty: Medium
Diagnostic time: 0.5-2.0 hours
Similar codes
Repair manuals
Manual library for ALFA ROMEO
89
Browse 89 ALFA ROMEO manuals: repair procedures, diagnostics, wiring diagrams, component locations, service data and Labor Times by year, model and trim.
ALFA ROMEO
-
ALFA ROMEO: 2024
-
ALFA ROMEO: 2023
-
Stelvio
-
ALFA ROMEO: 2022
-
Stelvio
-
ALFA ROMEO: 2021
-
Stelvio
-
ALFA ROMEO: 2020
Your experience will help others
+100 karma for a short comment :)
Was this AI description helpful?
Your feedback helps improve AI descriptions.
👍 Like
0
👎 Dislike
0
Send to email
Code
B1351
FIAT
B — Body
Ignition key-in-start switch short to positive
AI status
Completed
Completed
100%
Causes
- Chafed or damaged wiring harness with insulation worn to battery positive
- Corroded or loose connector at the ignition switch or BCM
- Faulty ignition key-in-start (ignition position) switch assembly
- Shorted splice or aftermarket accessory tied into the ignition feed
- Water ingress or contamination in switch/connector
- Intermittent BCM/control module hardware or ground fault
Symptoms
- Key position warnings or incorrect instrument cluster messages
- Starter engages unexpectedly or vehicle won’t crank when key turned
- Accessories powered when key is off, or inability to turn off accessories
- Possible fuse blow or repeated BCM faults
- Intermittent no-start or parasitic battery drain
What to check
- Scan vehicle and record freeze-frame data and related codes before clearing
- Visually inspect ignition switch connector, harness routing and nearby wiring for damage or aftermarket taps
- Check for corrosion, pushed pins, and proper connector mating at the switch and BCM
- Measure voltage at the ignition switch signal pin with key in OFF/ACC/ON/START positions
- Disconnect ignition switch connector and see if the fault clears or changes
- Perform wiggle test while monitoring the signal to reproduce the fault
Signal parameters
- Ignition signal open (expected): ~0–1 V (no key position contact)
- Ignition signal closed (ACC/ON/START): battery voltage ~11–14.5 V when switch contact is made
- Short-to-positive condition: signal measured at or near battery voltage in OFF position
- Intermittent short: fluctuating voltage between ~0 V and battery voltage during movement or vibration
Diagnostic algorithm
- Connect a scanner, read and record B1351 and any related codes and freeze-frame data.
- Inspect the ignition switch connector and harness for visible damage, corrosion or aftermarket splices.
- With ignition OFF, measure voltage at the ignition switch signal terminal. A steady battery voltage in OFF indicates a short to positive.
- Disconnect the ignition switch connector. If the code clears or the signal drops to ~0 V with the connector removed, suspect switch or harness between connector and BCM.
- If the signal remains high with the switch disconnected, trace and isolate the harness toward the BCM — look for a contact to battery feed or pinned terminal fault.
- Perform continuity and resistance checks between the ignition signal wire and battery positive, and between the signal wire and BCM pin using wiring diagrams. Repair any chafed wiring or shorted splices.
- Reconnect and operate the switch through all positions while monitoring voltage; replace the ignition switch assembly if internal contacts are faulty or stuck.
- After repairs, clear codes and retest for intermittent faults. If wiring and switch check good but code persists, consider BCM connector inspection and module diagnosis or replacement per manufacturer procedure.
- Safety note: Prevent unexpected starter engagement while testing. Follow OEM safety procedures when disconnecting electrical components or replacing modules.
Likely causes
- Ignition switch contact stuck or welded closed, holding the circuit at battery voltage
- Pin pushed out or terminal touching positive supply in connector
- Repair or accessory wiring incorrectly connected to ignition feed
- Damaged insulation where harness passes near battery/engine
- Corrosion inside connector making intermittent short to +B
Fault status
Status
B1351 — Ignition key-in-start switch circuit short to positive detected by BCM (ignition position signal held at battery voltage when it should be open).
Repair difficulty: Medium
Diagnostic time: 0.5-2.0 hours
Similar codes
Repair manuals
Manual library for FIAT
26
Browse 26 FIAT manuals: repair procedures, diagnostics, wiring diagrams, component locations, service data and Labor Times by year, model and trim.
FIAT
-
FIAT: 2022
-
500X
-
-
FIAT: 2021
-
500X
-
Your experience will help others
+100 karma for a short comment :)
Was this AI description helpful?
Your feedback helps improve AI descriptions.
👍 Like
0
👎 Dislike
0
Send to email
Code
B1351
LAND ROVER
B — Body
Left front - foot shock absorber motor
AI status
Completed
Completed
100%
Causes
- Chafed or damaged wiring harness with insulation worn to battery positive
- Corroded or loose connector at the ignition switch or BCM
- Faulty ignition key-in-start (ignition position) switch assembly
- Shorted splice or aftermarket accessory tied into the ignition feed
- Water ingress or contamination in switch/connector
- Intermittent BCM/control module hardware or ground fault
Symptoms
- Key position warnings or incorrect instrument cluster messages
- Starter engages unexpectedly or vehicle won’t crank when key turned
- Accessories powered when key is off, or inability to turn off accessories
- Possible fuse blow or repeated BCM faults
- Intermittent no-start or parasitic battery drain
What to check
- Scan vehicle and record freeze-frame data and related codes before clearing
- Visually inspect ignition switch connector, harness routing and nearby wiring for damage or aftermarket taps
- Check for corrosion, pushed pins, and proper connector mating at the switch and BCM
- Measure voltage at the ignition switch signal pin with key in OFF/ACC/ON/START positions
- Disconnect ignition switch connector and see if the fault clears or changes
- Perform wiggle test while monitoring the signal to reproduce the fault
Signal parameters
- Ignition signal open (expected): ~0–1 V (no key position contact)
- Ignition signal closed (ACC/ON/START): battery voltage ~11–14.5 V when switch contact is made
- Short-to-positive condition: signal measured at or near battery voltage in OFF position
- Intermittent short: fluctuating voltage between ~0 V and battery voltage during movement or vibration
Diagnostic algorithm
- Connect a scanner, read and record B1351 and any related codes and freeze-frame data.
- Inspect the ignition switch connector and harness for visible damage, corrosion or aftermarket splices.
- With ignition OFF, measure voltage at the ignition switch signal terminal. A steady battery voltage in OFF indicates a short to positive.
- Disconnect the ignition switch connector. If the code clears or the signal drops to ~0 V with the connector removed, suspect switch or harness between connector and BCM.
- If the signal remains high with the switch disconnected, trace and isolate the harness toward the BCM — look for a contact to battery feed or pinned terminal fault.
- Perform continuity and resistance checks between the ignition signal wire and battery positive, and between the signal wire and BCM pin using wiring diagrams. Repair any chafed wiring or shorted splices.
- Reconnect and operate the switch through all positions while monitoring voltage; replace the ignition switch assembly if internal contacts are faulty or stuck.
- After repairs, clear codes and retest for intermittent faults. If wiring and switch check good but code persists, consider BCM connector inspection and module diagnosis or replacement per manufacturer procedure.
- Safety note: Prevent unexpected starter engagement while testing. Follow OEM safety procedures when disconnecting electrical components or replacing modules.
Likely causes
- Ignition switch contact stuck or welded closed, holding the circuit at battery voltage
- Pin pushed out or terminal touching positive supply in connector
- Repair or accessory wiring incorrectly connected to ignition feed
- Damaged insulation where harness passes near battery/engine
- Corrosion inside connector making intermittent short to +B
Fault status
Status
B1351 — Ignition key-in-start switch circuit short to positive detected by BCM (ignition position signal held at battery voltage when it should be open).
Repair difficulty: Medium
Diagnostic time: 0.5-2.0 hours
Similar codes
Repair manuals
Manual library for LAND ROVER
320
Browse 320 LAND ROVER manuals: repair procedures, diagnostics, wiring diagrams, component locations, service data and Labor Times by year, model and trim.
LAND ROVER
-
LAND ROVER: 2022
-
Defender
- 90
- 90
- 90 S
- 90 S
- 90 V8
- 90 V8
- 90 V8 Carpathian Edition
- 90 V8 Carpathian Edition
- 90 X
- 90 X
- 90 X-Dynamic HSE
- 90 X-Dynamic HSE
- 90 X-Dynamic S
- 90 X-Dynamic S
- 90 X-Dynamic SE
- 90 X-Dynamic SE
- 110
- 110
- 110 S
- 110 S
- 110 SE
- 110 SE
- 110 V8
- 110 V8
- 110 V8 Carpathian Edition
- 110 V8 Carpathian Edition
- 110 X
- 110 X
- 110 X-Dynamic SE
- 110 X-Dynamic SE
- 110 XS Edition
- 110 XS Edition
-
Discovery
- R-Dynamic HSE
- R-Dynamic HSE
- R-Dynamic S, 2.0L Eng VIN X · 2.0L Eng VIN X2022: Discovery R-Dynamic S
- R-Dynamic S, 2.0L Eng VIN X · 2.0L Eng VIN X2022: Discovery R-Dynamic S
- R-Dynamic S, 3.0L Eng VIN U · 3.0L Eng VIN U2022: Discovery R-Dynamic S
- R-Dynamic S, 3.0L Eng VIN U · 3.0L Eng VIN U2022: Discovery R-Dynamic S
- S
- S
-
Discovery Sport
-
Range Rover
- Autobiography, 4.4L Eng VIN 7 · 4.4L Eng VIN 72022: Range Rover Autobiography
- Autobiography, 4.4L Eng VIN 7 · 4.4L Eng VIN 72022: Range Rover Autobiography
- Autobiography, 5.0L Eng VIN E · 5.0L Eng VIN E2022: Range Rover Autobiography
- Autobiography, 5.0L Eng VIN E · 5.0L Eng VIN E2022: Range Rover Autobiography
- 2022 Range Rover Base
- 2022 Range Rover Base
- First Edition
- First Edition
- HSE Westminster, 3.0L Eng VIN U · 3.0L Eng VIN U2022: Range Rover HSE Westminster
- HSE Westminster, 3.0L Eng VIN U · 3.0L Eng VIN U2022: Range Rover HSE Westminster
- HSE Westminster, 5.0L Eng VIN E · 5.0L Eng VIN E2022: Range Rover HSE Westminster
- HSE Westminster, 5.0L Eng VIN E · 5.0L Eng VIN E2022: Range Rover HSE Westminster
- SE, 3.0L Eng VIN U · 3.0L Eng VIN U2022: Range Rover SE
- SE, 3.0L Eng VIN U · 3.0L Eng VIN U2022: Range Rover SE
- SE, 4.4L Eng VIN 7 · 4.4L Eng VIN 72022: Range Rover SE
- SE, 4.4L Eng VIN 7 · 4.4L Eng VIN 72022: Range Rover SE
- SV
- SV
- SVAutobiography
- SVAutobiography
- SVAutobiography Dynamic
- SVAutobiography Dynamic
- SVAutobiography Dynamic Blk.
- SVAutobiography Dynamic Blk.
-
Range Rover Evoque
-
Range Rover Velar
- R-Dynamic HSE
- R-Dynamic HSE
- R-Dynamic S, 2.0L Eng VIN X · 2.0L Eng VIN X2022: Range Rover Velar R-Dynamic S
- R-Dynamic S, 2.0L Eng VIN X · 2.0L Eng VIN X2022: Range Rover Velar R-Dynamic S
- R-Dynamic S, 3.0L Eng VIN U · 3.0L Eng VIN U2022: Range Rover Velar R-Dynamic S
- R-Dynamic S, 3.0L Eng VIN U · 3.0L Eng VIN U2022: Range Rover Velar R-Dynamic S
- S, 2.0L Eng VIN X · 2.0L Eng VIN X2022: Range Rover Velar S
- S, 2.0L Eng VIN X · 2.0L Eng VIN X2022: Range Rover Velar S
- S, 3.0L Eng VIN U · 3.0L Eng VIN U2022: Range Rover Velar S
- S, 3.0L Eng VIN U · 3.0L Eng VIN U2022: Range Rover Velar S
-
-
LAND ROVER: 2021
-
Discovery
- R-Dynamic HSE
- R-Dynamic HSE
- R-Dynamic S, 2.0L Eng VIN X · 2.0L Eng VIN X2021: Discovery R-Dynamic S
- R-Dynamic S, 2.0L Eng VIN X · 2.0L Eng VIN X2021: Discovery R-Dynamic S
- R-Dynamic S, 3.0L Eng VIN U · 3.0L Eng VIN U2021: Discovery R-Dynamic S
- R-Dynamic S, 3.0L Eng VIN U · 3.0L Eng VIN U2021: Discovery R-Dynamic S
- S
- S
-
Discovery Sport
-
Range Rover
- Autobiography, 2.0L Eng VIN Y · 2.0L Eng VIN Y2021: Range Rover Autobiography
- Autobiography, 2.0L Eng VIN Y · 2.0L Eng VIN Y2021: Range Rover Autobiography
- Autobiography Fifty Edition
- Autobiography Fifty Edition
- 2021 Range Rover Base
- 2021 Range Rover Base
- HSE, 2.0L Eng VIN Y · 2.0L Eng VIN Y2021: Range Rover HSE
- HSE, 2.0L Eng VIN Y · 2.0L Eng VIN Y2021: Range Rover HSE
- HSE, 3.0L Eng VIN K · 3.0L Eng VIN K2021: Range Rover HSE
- HSE, 3.0L Eng VIN K · 3.0L Eng VIN K2021: Range Rover HSE
- HSE Westminster, 3.0L Eng VIN U · 3.0L Eng VIN U2021: Range Rover HSE Westminster
- HSE Westminster, 3.0L Eng VIN U · 3.0L Eng VIN U2021: Range Rover HSE Westminster
- HSE Westminster, 5.0L Eng VIN E · 5.0L Eng VIN E2021: Range Rover HSE Westminster
- HSE Westminster, 5.0L Eng VIN E · 5.0L Eng VIN E2021: Range Rover HSE Westminster
- SVAutobiography
- SVAutobiography
- SVAutobiography Dynamic
- SVAutobiography Dynamic
- SVAutobiography Dynamic Blk.
- SVAutobiography Dynamic Blk.
-
Range Rover Evoque
-
Range Rover Sport
- Autobiography, 2.0L Eng VIN Y · 2.0L Eng VIN Y2021: Range Rover Sport Autobiography
- Autobiography, 2.0L Eng VIN Y · 2.0L Eng VIN Y2021: Range Rover Sport Autobiography
- Autobiography, 5.0L Eng VIN E · 5.0L Eng VIN E2021: Range Rover Sport Autobiography
- Autobiography, 5.0L Eng VIN E · 5.0L Eng VIN E2021: Range Rover Sport Autobiography
- Autobiography Dynamic, 2.0L Eng VIN Y · 2.0L Eng VIN Y2021: Range Rover Sport Autobiography Dynamic
- Autobiography Dynamic, 2.0L Eng VIN Y · 2.0L Eng VIN Y2021: Range Rover Sport Autobiography Dynamic
- Autobiography Dynamic, 5.0L Eng VIN E · 5.0L Eng VIN E2021: Range Rover Sport Autobiography Dynamic
- Autobiography Dynamic, 5.0L Eng VIN E · 5.0L Eng VIN E2021: Range Rover Sport Autobiography Dynamic
- HSE Dynamic
- HSE Dynamic
- HSE Silver Edition, 2.0L Eng VIN Y · 2.0L Eng VIN Y2021: Range Rover Sport HSE Silver Edition
- HSE Silver Edition, 2.0L Eng VIN Y · 2.0L Eng VIN Y2021: Range Rover Sport HSE Silver Edition
- HSE Silver Edition, 3.0L Eng VIN K · 3.0L Eng VIN K2021: Range Rover Sport HSE Silver Edition
- HSE Silver Edition, 3.0L Eng VIN K · 3.0L Eng VIN K2021: Range Rover Sport HSE Silver Edition
- HSE Silver Edition, 3.0L Eng VIN U · 3.0L Eng VIN U2021: Range Rover Sport HSE Silver Edition
- HSE Silver Edition, 3.0L Eng VIN U · 3.0L Eng VIN U2021: Range Rover Sport HSE Silver Edition
- HST
- HST
- SE
- SE
- SVR
- SVR
- SVR Carbon Edition
- SVR Carbon Edition
-
Range Rover Velar
- R-Dynamic HSE
- R-Dynamic HSE
- R-Dynamic S, 2.0L Eng VIN X · 2.0L Eng VIN X2021: Range Rover Velar R-Dynamic S
- R-Dynamic S, 2.0L Eng VIN X · 2.0L Eng VIN X2021: Range Rover Velar R-Dynamic S
- R-Dynamic S, 3.0L Eng VIN U · 3.0L Eng VIN U2021: Range Rover Velar R-Dynamic S
- R-Dynamic S, 3.0L Eng VIN U · 3.0L Eng VIN U2021: Range Rover Velar R-Dynamic S
- S, 2.0L Eng VIN X · 2.0L Eng VIN X2021: Range Rover Velar S
- S, 2.0L Eng VIN X · 2.0L Eng VIN X2021: Range Rover Velar S
- S, 3.0L Eng VIN U · 3.0L Eng VIN U2021: Range Rover Velar S
- S, 3.0L Eng VIN U · 3.0L Eng VIN U2021: Range Rover Velar S
-
LAND ROVER: 2020
-
Defender
- 90 First Edition
- 90 First Edition
- 110 First Edition
- 110 First Edition
- 110 HSE
- 110 HSE
- 110 S
- 110 S
- 110 SE
- 110 SE
- 110 X
- 110 X
- 110, 2.0L Eng VIN X · 2.0L Eng VIN X2020: Defender 110
- 110, 2.0L Eng VIN X · 2.0L Eng VIN X2020: Defender 110
- 110, 3.0L Eng VIN U · 3.0L Eng VIN U2020: Defender 110
- 110, 3.0L Eng VIN U · 3.0L Eng VIN U2020: Defender 110
-
Discovery
- HSE, 3.0L Eng VIN K · 3.0L Eng VIN K2020: Discovery HSE
- HSE, 3.0L Eng VIN K · 3.0L Eng VIN K2020: Discovery HSE
- HSE, 3.0L Eng VIN V · 3.0L Eng VIN V2020: Discovery HSE
- HSE, 3.0L Eng VIN V · 3.0L Eng VIN V2020: Discovery HSE
- HSE Luxury, 3.0L Eng VIN K · 3.0L Eng VIN K2020: Discovery HSE Luxury
- HSE Luxury, 3.0L Eng VIN K · 3.0L Eng VIN K2020: Discovery HSE Luxury
- HSE Luxury, 3.0L Eng VIN V · 3.0L Eng VIN V2020: Discovery HSE Luxury
- HSE Luxury, 3.0L Eng VIN V · 3.0L Eng VIN V2020: Discovery HSE Luxury
- Landmark
- Landmark
- SE, 3.0L Eng VIN K · 3.0L Eng VIN K2020: Discovery SE
- SE, 3.0L Eng VIN K · 3.0L Eng VIN K2020: Discovery SE
- SE, 3.0L Eng VIN V · 3.0L Eng VIN V2020: Discovery SE
- SE, 3.0L Eng VIN V · 3.0L Eng VIN V2020: Discovery SE
-
Range Rover
- Autobiography
- Autobiography
- Base, 3.0L Eng VIN K · 3.0L Eng VIN K2020: Range Rover Base
- Base, 3.0L Eng VIN K · 3.0L Eng VIN K2020: Range Rover Base
- Base, 3.0L Eng VIN U · 3.0L Eng VIN U2020: Range Rover Base
- Base, 3.0L Eng VIN U · 3.0L Eng VIN U2020: Range Rover Base
- HSE, 2.0L Eng VIN Y · 2.0L Eng VIN Y2020: Range Rover HSE
- HSE, 2.0L Eng VIN Y · 2.0L Eng VIN Y2020: Range Rover HSE
- HSE, 3.0L Eng VIN K · 3.0L Eng VIN K2020: Range Rover HSE
- HSE, 3.0L Eng VIN K · 3.0L Eng VIN K2020: Range Rover HSE
- HSE, 3.0L Eng VIN U · 3.0L Eng VIN U2020: Range Rover HSE
- HSE, 3.0L Eng VIN U · 3.0L Eng VIN U2020: Range Rover HSE
- HSE, 5.0L Eng VIN E · 5.0L Eng VIN E2020: Range Rover HSE
- HSE, 5.0L Eng VIN E · 5.0L Eng VIN E2020: Range Rover HSE
- SVAutobiography
- SVAutobiography
- SVAutobiography Dynamic
- SVAutobiography Dynamic
-
Range Rover Evoque
-
Range Rover Sport
- Autobiography Dynamic, 2.0L Eng VIN Y · 2.0L Eng VIN Y2020: Range Rover Sport Autobiography Dynamic
- Autobiography Dynamic, 2.0L Eng VIN Y · 2.0L Eng VIN Y2020: Range Rover Sport Autobiography Dynamic
- Autobiography Dynamic, 5.0L Eng VIN E · 5.0L Eng VIN E2020: Range Rover Sport Autobiography Dynamic
- Autobiography Dynamic, 5.0L Eng VIN E · 5.0L Eng VIN E2020: Range Rover Sport Autobiography Dynamic
- HSE, 3.0L Eng VIN K · 3.0L Eng VIN K2020: Range Rover Sport HSE
- HSE, 3.0L Eng VIN K · 3.0L Eng VIN K2020: Range Rover Sport HSE
- HSE, 3.0L Eng VIN U · 3.0L Eng VIN U2020: Range Rover Sport HSE
- HSE, 3.0L Eng VIN U · 3.0L Eng VIN U2020: Range Rover Sport HSE
- HSE, 5.0L Eng VIN E · 5.0L Eng VIN E2020: Range Rover Sport HSE
- HSE, 5.0L Eng VIN E · 5.0L Eng VIN E2020: Range Rover Sport HSE
- HSE Dynamic
- HSE Dynamic
- HSE PHEV
- HSE PHEV
- HST
- HST
- SE, 3.0L Eng VIN K · 3.0L Eng VIN K2020: Range Rover Sport SE
- SE, 3.0L Eng VIN K · 3.0L Eng VIN K2020: Range Rover Sport SE
- SE, 3.0L Eng VIN U · 3.0L Eng VIN U2020: Range Rover Sport SE
- SE, 3.0L Eng VIN U · 3.0L Eng VIN U2020: Range Rover Sport SE
- SVR
- SVR
-
Range Rover Velar
- R-Dynamic HSE
- R-Dynamic HSE
- R-Dynamic S, 2.0L Eng VIN X · 2.0L Eng VIN X2020: Range Rover Velar R-Dynamic S
- R-Dynamic S, 2.0L Eng VIN X · 2.0L Eng VIN X2020: Range Rover Velar R-Dynamic S
- R-Dynamic S, 3.0L Eng VIN V · 3.0L Eng VIN V2020: Range Rover Velar R-Dynamic S
- R-Dynamic S, 3.0L Eng VIN V · 3.0L Eng VIN V2020: Range Rover Velar R-Dynamic S
- S, 2.0L Eng VIN X · 2.0L Eng VIN X2020: Range Rover Velar S
- S, 2.0L Eng VIN X · 2.0L Eng VIN X2020: Range Rover Velar S
- S, 3.0L Eng VIN V · 3.0L Eng VIN V2020: Range Rover Velar S
- S, 3.0L Eng VIN V · 3.0L Eng VIN V2020: Range Rover Velar S
- SVAutobiography Dyn.
- SVAutobiography Dyn.
-
Your experience will help others
+100 karma for a short comment :)
Was this AI description helpful?
Your feedback helps improve AI descriptions.
👍 Like
0
👎 Dislike
0
Send to email
Code
B1351
Other
B — Body
Ignition Key-In Circuit Short To Battery
AI status
Completed
Completed
100%
Causes
- Chafed or damaged wiring harness with insulation worn to battery positive
- Corroded or loose connector at the ignition switch or BCM
- Faulty ignition key-in-start (ignition position) switch assembly
- Shorted splice or aftermarket accessory tied into the ignition feed
- Water ingress or contamination in switch/connector
- Intermittent BCM/control module hardware or ground fault
Symptoms
- Key position warnings or incorrect instrument cluster messages
- Starter engages unexpectedly or vehicle won’t crank when key turned
- Accessories powered when key is off, or inability to turn off accessories
- Possible fuse blow or repeated BCM faults
- Intermittent no-start or parasitic battery drain
What to check
- Scan vehicle and record freeze-frame data and related codes before clearing
- Visually inspect ignition switch connector, harness routing and nearby wiring for damage or aftermarket taps
- Check for corrosion, pushed pins, and proper connector mating at the switch and BCM
- Measure voltage at the ignition switch signal pin with key in OFF/ACC/ON/START positions
- Disconnect ignition switch connector and see if the fault clears or changes
- Perform wiggle test while monitoring the signal to reproduce the fault
Signal parameters
- Ignition signal open (expected): ~0–1 V (no key position contact)
- Ignition signal closed (ACC/ON/START): battery voltage ~11–14.5 V when switch contact is made
- Short-to-positive condition: signal measured at or near battery voltage in OFF position
- Intermittent short: fluctuating voltage between ~0 V and battery voltage during movement or vibration
Diagnostic algorithm
- Connect a scanner, read and record B1351 and any related codes and freeze-frame data.
- Inspect the ignition switch connector and harness for visible damage, corrosion or aftermarket splices.
- With ignition OFF, measure voltage at the ignition switch signal terminal. A steady battery voltage in OFF indicates a short to positive.
- Disconnect the ignition switch connector. If the code clears or the signal drops to ~0 V with the connector removed, suspect switch or harness between connector and BCM.
- If the signal remains high with the switch disconnected, trace and isolate the harness toward the BCM — look for a contact to battery feed or pinned terminal fault.
- Perform continuity and resistance checks between the ignition signal wire and battery positive, and between the signal wire and BCM pin using wiring diagrams. Repair any chafed wiring or shorted splices.
- Reconnect and operate the switch through all positions while monitoring voltage; replace the ignition switch assembly if internal contacts are faulty or stuck.
- After repairs, clear codes and retest for intermittent faults. If wiring and switch check good but code persists, consider BCM connector inspection and module diagnosis or replacement per manufacturer procedure.
- Safety note: Prevent unexpected starter engagement while testing. Follow OEM safety procedures when disconnecting electrical components or replacing modules.
Likely causes
- Ignition switch contact stuck or welded closed, holding the circuit at battery voltage
- Pin pushed out or terminal touching positive supply in connector
- Repair or accessory wiring incorrectly connected to ignition feed
- Damaged insulation where harness passes near battery/engine
- Corrosion inside connector making intermittent short to +B
Fault status
Status
B1351 — Ignition key-in-start switch circuit short to positive detected by BCM (ignition position signal held at battery voltage when it should be open).
Repair difficulty: Medium
Diagnostic time: 0.5-2.0 hours
Similar codes
Repair manuals
Brands with available manuals
8,885
The library contains 8,885 repair and diagnostic manuals. Choose a brand to open the full manual tree by year, model and trim.
Your experience will help others
+100 karma for a short comment :)
Was this AI description helpful?
Your feedback helps improve AI descriptions.
👍 Like
0
👎 Dislike
0
Send to email