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Home / DTC / B2103 — Rear Vertical Down Switch Failed

B2103 — Rear Vertical Down Switch Failed

Detailed page for trouble code B2103.

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22,491specific
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Code

B2103

HUMMER B — Body

Rear Vertical Down Switch Failed

Brand: HUMMER
Type: B — Body
AI status
Completed
ready
Completed 100%
Page language: EN

Causes

  • Failed rear vertical down switch (internal contact or mechanical failure)
  • Open, short, or damaged wiring in the switch circuit
  • Poor or corroded connector or terminal at the switch
  • Failed or intermittent ground or power supply to the switch
  • Faulty body control module (BCM) or input module
  • Related fuse blown or poor fuse connection

Symptoms

  • DTC B2103 stored in memory and possibly a related message/warning displayed
  • Associated rear component (e.g., tailgate, liftgate, window or convertible section) will not register 'down' position or will not complete down travel
  • Intermittent or no operation of the rear function tied to the switch
  • Possible illumination of body system warning lamps or messages
  • Operation may be inconsistent (works sometimes, fails other times)

What to check

  • Scan tool: read DTCs, freeze frame, and live data for the rear vertical down switch input/state
  • Visual inspection of switch, actuator and surrounding mechanism for damage or binding
  • Inspect the switch connector for corrosion, bent pins, or water ingress
  • Check related fuses and power feeds for the circuit
  • Backprobe switch connector to confirm reference voltage, supply, and ground
  • Wiggle test the harness while monitoring switch signal for intermittent changes

Signal parameters

  • Supply voltage to switch (approx. battery voltage, ~12 V) — verify present
  • Switch reference or pull-up voltage (if used) — usually ignition or module supplied
  • Switch output signal state (open/closed or high/low) as seen by BCM
  • Contact resistance of switch when actuated (ohms, near 0 Ω for closed)
  • Open-circuit resistance when switch released (infinite/OL)
  • CAN/LIN message indicating switch state (if applicable)

Diagnostic algorithm

  1. Connect a scan tool, read and record B2103 and any related codes; note freeze frame and live data while operating the rear mechanism.
  2. Attempt to reproduce the fault by cycling the rear component to the down position while watching the switch input on the scanner.
  3. Perform a visual inspection of the switch, actuator, harness routing, and mating connector for physical damage or contamination.
  4. Verify relevant fuses and apply battery voltage to the switch supply circuit; check for proper ground at the switch connector.
  5. Backprobe the switch connector with a multimeter: confirm supply voltage, reference/pull-up voltage, and that the switch changes state (open/closed) when actuated.
  6. If wiring or signal is intermittent or incorrect, disconnect the switch and measure continuity/resistance between the switch connector and BCM input pin(s); repair any opens, shorts, or high resistance.
  7. If the harness and wiring check good, bench-test or replace the switch and re-test operation; some switches are serviceable only by replacement.
  8. If replacement switch does not clear the issue, inspect BCM input circuits and connector; consider swapping or reprogramming module only after confirming wiring and switch health.
  9. After repair, clear codes and verify correct operation through several cycles; confirm no return of B2103 and that live data shows proper switch states.

Likely causes

  • Switch has internal contact failure or stuck actuator
  • Corroded/loose connector at the switch or BCM
  • Broken or chafed harness leading to the switch (open or short to ground/power)
  • Missing or poor ground at chassis or module
  • Intermittent BCM input circuit (module fault) — less common

Fault status

⚠️ Status
Stored when the BCM detects an invalid, open, or shorted signal from the Rear Vertical Down Switch circuit. May be set as active, pending, or intermittent depending on conditions. Inspection of switch, wiring, connectors, and module input required.
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 0.5-2.0 hours

Similar codes

B2100 B2101 B2102 B2104 B2105 B2135
Repair manuals

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Code

B2103

LAND ROVER B — Body

Antenna not connected

Brand: LAND ROVER
Type: B — Body
AI status
Completed
ready
Completed 100%
Page language: EN

Causes

  • Failed rear vertical down switch (internal contact or mechanical failure)
  • Open, short, or damaged wiring in the switch circuit
  • Poor or corroded connector or terminal at the switch
  • Failed or intermittent ground or power supply to the switch
  • Faulty body control module (BCM) or input module
  • Related fuse blown or poor fuse connection

Symptoms

  • DTC B2103 stored in memory and possibly a related message/warning displayed
  • Associated rear component (e.g., tailgate, liftgate, window or convertible section) will not register 'down' position or will not complete down travel
  • Intermittent or no operation of the rear function tied to the switch
  • Possible illumination of body system warning lamps or messages
  • Operation may be inconsistent (works sometimes, fails other times)

What to check

  • Scan tool: read DTCs, freeze frame, and live data for the rear vertical down switch input/state
  • Visual inspection of switch, actuator and surrounding mechanism for damage or binding
  • Inspect the switch connector for corrosion, bent pins, or water ingress
  • Check related fuses and power feeds for the circuit
  • Backprobe switch connector to confirm reference voltage, supply, and ground
  • Wiggle test the harness while monitoring switch signal for intermittent changes

Signal parameters

  • Supply voltage to switch (approx. battery voltage, ~12 V) — verify present
  • Switch reference or pull-up voltage (if used) — usually ignition or module supplied
  • Switch output signal state (open/closed or high/low) as seen by BCM
  • Contact resistance of switch when actuated (ohms, near 0 Ω for closed)
  • Open-circuit resistance when switch released (infinite/OL)
  • CAN/LIN message indicating switch state (if applicable)

Diagnostic algorithm

  1. Connect a scan tool, read and record B2103 and any related codes; note freeze frame and live data while operating the rear mechanism.
  2. Attempt to reproduce the fault by cycling the rear component to the down position while watching the switch input on the scanner.
  3. Perform a visual inspection of the switch, actuator, harness routing, and mating connector for physical damage or contamination.
  4. Verify relevant fuses and apply battery voltage to the switch supply circuit; check for proper ground at the switch connector.
  5. Backprobe the switch connector with a multimeter: confirm supply voltage, reference/pull-up voltage, and that the switch changes state (open/closed) when actuated.
  6. If wiring or signal is intermittent or incorrect, disconnect the switch and measure continuity/resistance between the switch connector and BCM input pin(s); repair any opens, shorts, or high resistance.
  7. If the harness and wiring check good, bench-test or replace the switch and re-test operation; some switches are serviceable only by replacement.
  8. If replacement switch does not clear the issue, inspect BCM input circuits and connector; consider swapping or reprogramming module only after confirming wiring and switch health.
  9. After repair, clear codes and verify correct operation through several cycles; confirm no return of B2103 and that live data shows proper switch states.

Likely causes

  • Switch has internal contact failure or stuck actuator
  • Corroded/loose connector at the switch or BCM
  • Broken or chafed harness leading to the switch (open or short to ground/power)
  • Missing or poor ground at chassis or module
  • Intermittent BCM input circuit (module fault) — less common

Fault status

⚠️ Status
Stored when the BCM detects an invalid, open, or shorted signal from the Rear Vertical Down Switch circuit. May be set as active, pending, or intermittent depending on conditions. Inspection of switch, wiring, connectors, and module input required.
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 0.5-2.0 hours

Similar codes

B2100 B2101 B2102 B2104 B2105 B2135
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

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Code

B2103

Other B — Body

Antenna Not Connected

Brand: Other
Type: B — Body
AI status
Completed
ready
Completed 100%
Page language: EN

Causes

  • Failed rear vertical down switch (internal contact or mechanical failure)
  • Open, short, or damaged wiring in the switch circuit
  • Poor or corroded connector or terminal at the switch
  • Failed or intermittent ground or power supply to the switch
  • Faulty body control module (BCM) or input module
  • Related fuse blown or poor fuse connection

Symptoms

  • DTC B2103 stored in memory and possibly a related message/warning displayed
  • Associated rear component (e.g., tailgate, liftgate, window or convertible section) will not register 'down' position or will not complete down travel
  • Intermittent or no operation of the rear function tied to the switch
  • Possible illumination of body system warning lamps or messages
  • Operation may be inconsistent (works sometimes, fails other times)

What to check

  • Scan tool: read DTCs, freeze frame, and live data for the rear vertical down switch input/state
  • Visual inspection of switch, actuator and surrounding mechanism for damage or binding
  • Inspect the switch connector for corrosion, bent pins, or water ingress
  • Check related fuses and power feeds for the circuit
  • Backprobe switch connector to confirm reference voltage, supply, and ground
  • Wiggle test the harness while monitoring switch signal for intermittent changes

Signal parameters

  • Supply voltage to switch (approx. battery voltage, ~12 V) — verify present
  • Switch reference or pull-up voltage (if used) — usually ignition or module supplied
  • Switch output signal state (open/closed or high/low) as seen by BCM
  • Contact resistance of switch when actuated (ohms, near 0 Ω for closed)
  • Open-circuit resistance when switch released (infinite/OL)
  • CAN/LIN message indicating switch state (if applicable)

Diagnostic algorithm

  1. Connect a scan tool, read and record B2103 and any related codes; note freeze frame and live data while operating the rear mechanism.
  2. Attempt to reproduce the fault by cycling the rear component to the down position while watching the switch input on the scanner.
  3. Perform a visual inspection of the switch, actuator, harness routing, and mating connector for physical damage or contamination.
  4. Verify relevant fuses and apply battery voltage to the switch supply circuit; check for proper ground at the switch connector.
  5. Backprobe the switch connector with a multimeter: confirm supply voltage, reference/pull-up voltage, and that the switch changes state (open/closed) when actuated.
  6. If wiring or signal is intermittent or incorrect, disconnect the switch and measure continuity/resistance between the switch connector and BCM input pin(s); repair any opens, shorts, or high resistance.
  7. If the harness and wiring check good, bench-test or replace the switch and re-test operation; some switches are serviceable only by replacement.
  8. If replacement switch does not clear the issue, inspect BCM input circuits and connector; consider swapping or reprogramming module only after confirming wiring and switch health.
  9. After repair, clear codes and verify correct operation through several cycles; confirm no return of B2103 and that live data shows proper switch states.

Likely causes

  • Switch has internal contact failure or stuck actuator
  • Corroded/loose connector at the switch or BCM
  • Broken or chafed harness leading to the switch (open or short to ground/power)
  • Missing or poor ground at chassis or module
  • Intermittent BCM input circuit (module fault) — less common

Fault status

⚠️ Status
Stored when the BCM detects an invalid, open, or shorted signal from the Rear Vertical Down Switch circuit. May be set as active, pending, or intermittent depending on conditions. Inspection of switch, wiring, connectors, and module input required.
🟡 Repair difficulty: Medium
⏱️ Diagnostic time: 0.5-2.0 hours

Similar codes

B2100 B2101 B2102 B2104 B2105 B2135
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