P1419
Catalytic converter downstream temperature sensor short circuit to positive or open circuit
Causes
- Broken or shorted wiring in the sensor/ECU harness (short to battery/positive or open circuit)
- Corroded, loose or contaminated sensor connector pins
- Failed downstream catalytic converter temperature sensor (NTC/thermistor or sensor heater)
- Blown fuse or fault in an upstream relay supplying the sensor/heater circuit
- ECU internal fault (rare) or incorrect ECU grounding
Symptoms
- Malfunction Indicator Lamp (MIL) illuminated and P1419 stored
- Possible failed emissions test or active catalyst-related limp conditions
- Reduced feedback for catalyst control — erratic emissions control or fuel trims
- Noisy or intermittent diagnostic data from downstream temperature channel
- Possible limited driveability if ECU enters protective strategies (rare)
What to check
- Read DTCs and freeze-frame data with a scan tool; note pending vs stored status
- Visually inspect downstream sensor wiring, connector, and mounting for heat/chafe/corrosion
- Backprobe the sensor connector with ignition ON to check reference voltage and ground presence
- Measure sensor resistance (thermistor) at ambient temperature and compare to spec
- Check for continuity between the sensor signal/heater wires and battery positive (short) and to open circuit
- Measure heater circuit resistance (if applicable) and check for battery voltage supply when heater is commanded
Signal parameters
- Sensor type: typically an NTC thermistor element — resistance falls as temperature rises
- Expected behavior: sensor voltage varies with temperature (typical ECU input range ~0.1–5.0 V depending on temp and ECU reference — consult vehicle spec)
- Ambient/room temperature resistance is usually in the kilo-ohm range (manufacturer-specific); consult Citroën service data for exact values
- Heater circuit (if present): feed should show battery voltage when active and low ohm resistance across heater element (spec varies by sensor)
- P1419 indicates either an open circuit (very high resistance/infinite) or a short to positive (voltage stuck near battery voltage) on sensor or heater circuit
Diagnostic algorithm
- Connect a diagnostic scan tool, confirm P1419 and any related codes; record freeze-frame and live downstream temperature values.
- Visually inspect sensor, connector and wiring from sensor to ECU for heat damage, chafing, pin corrosion, or rodent damage; repair obvious damage.
- With ignition ON (engine OFF), backprobe connector: check for proper reference/return voltages per wiring diagram; note if voltage is stuck at battery (short to positive) or absent (open).
- Disconnect sensor and measure thermistor resistance at ambient; compare to manufacturer spec. Infinite/open = thermistor failure; short/very low resistance may indicate heater short.
- Check for short to battery: measure continuity between signal/heater wires and battery positive; isolate sections of harness to find short location.
- Measure heater circuit resistance (if equipped) between heater pins and verify battery feed when heater commanded by ECU (use scan tool to actuate if available).
- Wiggle harness and connectors while monitoring live data to find intermittent faults; repair or replace damaged wiring or connectors.
- If wiring and connectors test OK and replacement sensor available, fit a known-good sensor and re-test.
- Clear codes, road test and re-scan. If code returns and wiring checks are OK, consider ECU fault and consult manufacturer guidance before replacement.
Likely causes
- Damaged insulation allowing sensor signal or heater wire to contact battery feed
- Connector corrosion or pin damage at the downstream sensor
- Open thermistor element or broken heater winding inside the sensor
- Faulty sensor replacement or installation fault
- Intermittent harness damage near exhaust, mounting bracket, or flex areas
Fault status
Similar codes
P1419
2 ND AIR JINECTION V/V
Causes
- Broken or shorted wiring in the sensor/ECU harness (short to battery/positive or open circuit)
- Corroded, loose or contaminated sensor connector pins
- Failed downstream catalytic converter temperature sensor (NTC/thermistor or sensor heater)
- Blown fuse or fault in an upstream relay supplying the sensor/heater circuit
- ECU internal fault (rare) or incorrect ECU grounding
Symptoms
- Malfunction Indicator Lamp (MIL) illuminated and P1419 stored
- Possible failed emissions test or active catalyst-related limp conditions
- Reduced feedback for catalyst control — erratic emissions control or fuel trims
- Noisy or intermittent diagnostic data from downstream temperature channel
- Possible limited driveability if ECU enters protective strategies (rare)
What to check
- Read DTCs and freeze-frame data with a scan tool; note pending vs stored status
- Visually inspect downstream sensor wiring, connector, and mounting for heat/chafe/corrosion
- Backprobe the sensor connector with ignition ON to check reference voltage and ground presence
- Measure sensor resistance (thermistor) at ambient temperature and compare to spec
- Check for continuity between the sensor signal/heater wires and battery positive (short) and to open circuit
- Measure heater circuit resistance (if applicable) and check for battery voltage supply when heater is commanded
Signal parameters
- Sensor type: typically an NTC thermistor element — resistance falls as temperature rises
- Expected behavior: sensor voltage varies with temperature (typical ECU input range ~0.1–5.0 V depending on temp and ECU reference — consult vehicle spec)
- Ambient/room temperature resistance is usually in the kilo-ohm range (manufacturer-specific); consult Citroën service data for exact values
- Heater circuit (if present): feed should show battery voltage when active and low ohm resistance across heater element (spec varies by sensor)
- P1419 indicates either an open circuit (very high resistance/infinite) or a short to positive (voltage stuck near battery voltage) on sensor or heater circuit
Diagnostic algorithm
- Connect a diagnostic scan tool, confirm P1419 and any related codes; record freeze-frame and live downstream temperature values.
- Visually inspect sensor, connector and wiring from sensor to ECU for heat damage, chafing, pin corrosion, or rodent damage; repair obvious damage.
- With ignition ON (engine OFF), backprobe connector: check for proper reference/return voltages per wiring diagram; note if voltage is stuck at battery (short to positive) or absent (open).
- Disconnect sensor and measure thermistor resistance at ambient; compare to manufacturer spec. Infinite/open = thermistor failure; short/very low resistance may indicate heater short.
- Check for short to battery: measure continuity between signal/heater wires and battery positive; isolate sections of harness to find short location.
- Measure heater circuit resistance (if equipped) between heater pins and verify battery feed when heater commanded by ECU (use scan tool to actuate if available).
- Wiggle harness and connectors while monitoring live data to find intermittent faults; repair or replace damaged wiring or connectors.
- If wiring and connectors test OK and replacement sensor available, fit a known-good sensor and re-test.
- Clear codes, road test and re-scan. If code returns and wiring checks are OK, consider ECU fault and consult manufacturer guidance before replacement.
Likely causes
- Damaged insulation allowing sensor signal or heater wire to contact battery feed
- Connector corrosion or pin damage at the downstream sensor
- Open thermistor element or broken heater winding inside the sensor
- Faulty sensor replacement or installation fault
- Intermittent harness damage near exhaust, mounting bracket, or flex areas
Fault status
Similar codes
Manual library for DAEWOO
Browse 75 DAEWOO manuals: repair procedures, diagnostics, wiring diagrams, component locations, service data and Labor Times by year, model and trim.
DAEWOO
-
DAEWOO: 2001
-
Leganza
-
DAEWOO: 2000
-
Leganza
-
DAEWOO: 1999
-
Lanos
- S, 2D Hatchback, Automatic
- S, 2D Hatchback, Standard
- S, 4D Sedan, Automatic
- S, 4D Sedan, Standard
- SE, 2D Hatchback, Automatic
- SE, 2D Hatchback, Standard
- SE, 4D Sedan, Automatic
- SE, 4D Sedan, Standard
- SX, 2D Hatchback, Automatic
- SX, 2D Hatchback, Standard
- SX, 4D Sedan, Automatic
- SX, 4D Sedan, Standard
-
Leganza
-
Nubira
- CDX, 4D Hatchback, Automatic
- CDX, 4D Hatchback, Standard
- CDX, 4D Sedan, Automatic
- CDX, 4D Sedan, Standard
- CDX, 4D Wagon, Automatic
- CDX, 4D Wagon, Standard
- SX, 4D Hatchback, Automatic
- SX, 4D Hatchback, Standard
- SX, 4D Sedan, Automatic
- SX, 4D Sedan, Standard
- SX, 4D Wagon, Automatic
- SX, 4D Wagon, Standard
-
P1419
Catalytic converter downstream temperature sensor short circuit to positive or open circuit
Causes
- Broken or shorted wiring in the sensor/ECU harness (short to battery/positive or open circuit)
- Corroded, loose or contaminated sensor connector pins
- Failed downstream catalytic converter temperature sensor (NTC/thermistor or sensor heater)
- Blown fuse or fault in an upstream relay supplying the sensor/heater circuit
- ECU internal fault (rare) or incorrect ECU grounding
Symptoms
- Malfunction Indicator Lamp (MIL) illuminated and P1419 stored
- Possible failed emissions test or active catalyst-related limp conditions
- Reduced feedback for catalyst control — erratic emissions control or fuel trims
- Noisy or intermittent diagnostic data from downstream temperature channel
- Possible limited driveability if ECU enters protective strategies (rare)
What to check
- Read DTCs and freeze-frame data with a scan tool; note pending vs stored status
- Visually inspect downstream sensor wiring, connector, and mounting for heat/chafe/corrosion
- Backprobe the sensor connector with ignition ON to check reference voltage and ground presence
- Measure sensor resistance (thermistor) at ambient temperature and compare to spec
- Check for continuity between the sensor signal/heater wires and battery positive (short) and to open circuit
- Measure heater circuit resistance (if applicable) and check for battery voltage supply when heater is commanded
Signal parameters
- Sensor type: typically an NTC thermistor element — resistance falls as temperature rises
- Expected behavior: sensor voltage varies with temperature (typical ECU input range ~0.1–5.0 V depending on temp and ECU reference — consult vehicle spec)
- Ambient/room temperature resistance is usually in the kilo-ohm range (manufacturer-specific); consult Citroën service data for exact values
- Heater circuit (if present): feed should show battery voltage when active and low ohm resistance across heater element (spec varies by sensor)
- P1419 indicates either an open circuit (very high resistance/infinite) or a short to positive (voltage stuck near battery voltage) on sensor or heater circuit
Diagnostic algorithm
- Connect a diagnostic scan tool, confirm P1419 and any related codes; record freeze-frame and live downstream temperature values.
- Visually inspect sensor, connector and wiring from sensor to ECU for heat damage, chafing, pin corrosion, or rodent damage; repair obvious damage.
- With ignition ON (engine OFF), backprobe connector: check for proper reference/return voltages per wiring diagram; note if voltage is stuck at battery (short to positive) or absent (open).
- Disconnect sensor and measure thermistor resistance at ambient; compare to manufacturer spec. Infinite/open = thermistor failure; short/very low resistance may indicate heater short.
- Check for short to battery: measure continuity between signal/heater wires and battery positive; isolate sections of harness to find short location.
- Measure heater circuit resistance (if equipped) between heater pins and verify battery feed when heater commanded by ECU (use scan tool to actuate if available).
- Wiggle harness and connectors while monitoring live data to find intermittent faults; repair or replace damaged wiring or connectors.
- If wiring and connectors test OK and replacement sensor available, fit a known-good sensor and re-test.
- Clear codes, road test and re-scan. If code returns and wiring checks are OK, consider ECU fault and consult manufacturer guidance before replacement.
Likely causes
- Damaged insulation allowing sensor signal or heater wire to contact battery feed
- Connector corrosion or pin damage at the downstream sensor
- Open thermistor element or broken heater winding inside the sensor
- Faulty sensor replacement or installation fault
- Intermittent harness damage near exhaust, mounting bracket, or flex areas
Fault status
Similar codes
P1419
Split Air 2 Circuit
Causes
- Broken or shorted wiring in the sensor/ECU harness (short to battery/positive or open circuit)
- Corroded, loose or contaminated sensor connector pins
- Failed downstream catalytic converter temperature sensor (NTC/thermistor or sensor heater)
- Blown fuse or fault in an upstream relay supplying the sensor/heater circuit
- ECU internal fault (rare) or incorrect ECU grounding
Symptoms
- Malfunction Indicator Lamp (MIL) illuminated and P1419 stored
- Possible failed emissions test or active catalyst-related limp conditions
- Reduced feedback for catalyst control — erratic emissions control or fuel trims
- Noisy or intermittent diagnostic data from downstream temperature channel
- Possible limited driveability if ECU enters protective strategies (rare)
What to check
- Read DTCs and freeze-frame data with a scan tool; note pending vs stored status
- Visually inspect downstream sensor wiring, connector, and mounting for heat/chafe/corrosion
- Backprobe the sensor connector with ignition ON to check reference voltage and ground presence
- Measure sensor resistance (thermistor) at ambient temperature and compare to spec
- Check for continuity between the sensor signal/heater wires and battery positive (short) and to open circuit
- Measure heater circuit resistance (if applicable) and check for battery voltage supply when heater is commanded
Signal parameters
- Sensor type: typically an NTC thermistor element — resistance falls as temperature rises
- Expected behavior: sensor voltage varies with temperature (typical ECU input range ~0.1–5.0 V depending on temp and ECU reference — consult vehicle spec)
- Ambient/room temperature resistance is usually in the kilo-ohm range (manufacturer-specific); consult Citroën service data for exact values
- Heater circuit (if present): feed should show battery voltage when active and low ohm resistance across heater element (spec varies by sensor)
- P1419 indicates either an open circuit (very high resistance/infinite) or a short to positive (voltage stuck near battery voltage) on sensor or heater circuit
Diagnostic algorithm
- Connect a diagnostic scan tool, confirm P1419 and any related codes; record freeze-frame and live downstream temperature values.
- Visually inspect sensor, connector and wiring from sensor to ECU for heat damage, chafing, pin corrosion, or rodent damage; repair obvious damage.
- With ignition ON (engine OFF), backprobe connector: check for proper reference/return voltages per wiring diagram; note if voltage is stuck at battery (short to positive) or absent (open).
- Disconnect sensor and measure thermistor resistance at ambient; compare to manufacturer spec. Infinite/open = thermistor failure; short/very low resistance may indicate heater short.
- Check for short to battery: measure continuity between signal/heater wires and battery positive; isolate sections of harness to find short location.
- Measure heater circuit resistance (if equipped) between heater pins and verify battery feed when heater commanded by ECU (use scan tool to actuate if available).
- Wiggle harness and connectors while monitoring live data to find intermittent faults; repair or replace damaged wiring or connectors.
- If wiring and connectors test OK and replacement sensor available, fit a known-good sensor and re-test.
- Clear codes, road test and re-scan. If code returns and wiring checks are OK, consider ECU fault and consult manufacturer guidance before replacement.
Likely causes
- Damaged insulation allowing sensor signal or heater wire to contact battery feed
- Connector corrosion or pin damage at the downstream sensor
- Open thermistor element or broken heater winding inside the sensor
- Faulty sensor replacement or installation fault
- Intermittent harness damage near exhaust, mounting bracket, or flex areas
Fault status
Similar codes
P1419
Split Air #2 Circuit Malfunction
Causes
- Broken or shorted wiring in the sensor/ECU harness (short to battery/positive or open circuit)
- Corroded, loose or contaminated sensor connector pins
- Failed downstream catalytic converter temperature sensor (NTC/thermistor or sensor heater)
- Blown fuse or fault in an upstream relay supplying the sensor/heater circuit
- ECU internal fault (rare) or incorrect ECU grounding
Symptoms
- Malfunction Indicator Lamp (MIL) illuminated and P1419 stored
- Possible failed emissions test or active catalyst-related limp conditions
- Reduced feedback for catalyst control — erratic emissions control or fuel trims
- Noisy or intermittent diagnostic data from downstream temperature channel
- Possible limited driveability if ECU enters protective strategies (rare)
What to check
- Read DTCs and freeze-frame data with a scan tool; note pending vs stored status
- Visually inspect downstream sensor wiring, connector, and mounting for heat/chafe/corrosion
- Backprobe the sensor connector with ignition ON to check reference voltage and ground presence
- Measure sensor resistance (thermistor) at ambient temperature and compare to spec
- Check for continuity between the sensor signal/heater wires and battery positive (short) and to open circuit
- Measure heater circuit resistance (if applicable) and check for battery voltage supply when heater is commanded
Signal parameters
- Sensor type: typically an NTC thermistor element — resistance falls as temperature rises
- Expected behavior: sensor voltage varies with temperature (typical ECU input range ~0.1–5.0 V depending on temp and ECU reference — consult vehicle spec)
- Ambient/room temperature resistance is usually in the kilo-ohm range (manufacturer-specific); consult Citroën service data for exact values
- Heater circuit (if present): feed should show battery voltage when active and low ohm resistance across heater element (spec varies by sensor)
- P1419 indicates either an open circuit (very high resistance/infinite) or a short to positive (voltage stuck near battery voltage) on sensor or heater circuit
Diagnostic algorithm
- Connect a diagnostic scan tool, confirm P1419 and any related codes; record freeze-frame and live downstream temperature values.
- Visually inspect sensor, connector and wiring from sensor to ECU for heat damage, chafing, pin corrosion, or rodent damage; repair obvious damage.
- With ignition ON (engine OFF), backprobe connector: check for proper reference/return voltages per wiring diagram; note if voltage is stuck at battery (short to positive) or absent (open).
- Disconnect sensor and measure thermistor resistance at ambient; compare to manufacturer spec. Infinite/open = thermistor failure; short/very low resistance may indicate heater short.
- Check for short to battery: measure continuity between signal/heater wires and battery positive; isolate sections of harness to find short location.
- Measure heater circuit resistance (if equipped) between heater pins and verify battery feed when heater commanded by ECU (use scan tool to actuate if available).
- Wiggle harness and connectors while monitoring live data to find intermittent faults; repair or replace damaged wiring or connectors.
- If wiring and connectors test OK and replacement sensor available, fit a known-good sensor and re-test.
- Clear codes, road test and re-scan. If code returns and wiring checks are OK, consider ECU fault and consult manufacturer guidance before replacement.
Likely causes
- Damaged insulation allowing sensor signal or heater wire to contact battery feed
- Connector corrosion or pin damage at the downstream sensor
- Open thermistor element or broken heater winding inside the sensor
- Faulty sensor replacement or installation fault
- Intermittent harness damage near exhaust, mounting bracket, or flex areas
Fault status
Similar codes
Brands with available manuals
The library contains 8,907 repair and diagnostic manuals. Choose a brand to open the full manual tree by year, model and trim.
P1419
Catalytic converter downstream temperature sensor short circuit to positive or open circuit
Causes
- Broken or shorted wiring in the sensor/ECU harness (short to battery/positive or open circuit)
- Corroded, loose or contaminated sensor connector pins
- Failed downstream catalytic converter temperature sensor (NTC/thermistor or sensor heater)
- Blown fuse or fault in an upstream relay supplying the sensor/heater circuit
- ECU internal fault (rare) or incorrect ECU grounding
Symptoms
- Malfunction Indicator Lamp (MIL) illuminated and P1419 stored
- Possible failed emissions test or active catalyst-related limp conditions
- Reduced feedback for catalyst control — erratic emissions control or fuel trims
- Noisy or intermittent diagnostic data from downstream temperature channel
- Possible limited driveability if ECU enters protective strategies (rare)
What to check
- Read DTCs and freeze-frame data with a scan tool; note pending vs stored status
- Visually inspect downstream sensor wiring, connector, and mounting for heat/chafe/corrosion
- Backprobe the sensor connector with ignition ON to check reference voltage and ground presence
- Measure sensor resistance (thermistor) at ambient temperature and compare to spec
- Check for continuity between the sensor signal/heater wires and battery positive (short) and to open circuit
- Measure heater circuit resistance (if applicable) and check for battery voltage supply when heater is commanded
Signal parameters
- Sensor type: typically an NTC thermistor element — resistance falls as temperature rises
- Expected behavior: sensor voltage varies with temperature (typical ECU input range ~0.1–5.0 V depending on temp and ECU reference — consult vehicle spec)
- Ambient/room temperature resistance is usually in the kilo-ohm range (manufacturer-specific); consult Citroën service data for exact values
- Heater circuit (if present): feed should show battery voltage when active and low ohm resistance across heater element (spec varies by sensor)
- P1419 indicates either an open circuit (very high resistance/infinite) or a short to positive (voltage stuck near battery voltage) on sensor or heater circuit
Diagnostic algorithm
- Connect a diagnostic scan tool, confirm P1419 and any related codes; record freeze-frame and live downstream temperature values.
- Visually inspect sensor, connector and wiring from sensor to ECU for heat damage, chafing, pin corrosion, or rodent damage; repair obvious damage.
- With ignition ON (engine OFF), backprobe connector: check for proper reference/return voltages per wiring diagram; note if voltage is stuck at battery (short to positive) or absent (open).
- Disconnect sensor and measure thermistor resistance at ambient; compare to manufacturer spec. Infinite/open = thermistor failure; short/very low resistance may indicate heater short.
- Check for short to battery: measure continuity between signal/heater wires and battery positive; isolate sections of harness to find short location.
- Measure heater circuit resistance (if equipped) between heater pins and verify battery feed when heater commanded by ECU (use scan tool to actuate if available).
- Wiggle harness and connectors while monitoring live data to find intermittent faults; repair or replace damaged wiring or connectors.
- If wiring and connectors test OK and replacement sensor available, fit a known-good sensor and re-test.
- Clear codes, road test and re-scan. If code returns and wiring checks are OK, consider ECU fault and consult manufacturer guidance before replacement.
Likely causes
- Damaged insulation allowing sensor signal or heater wire to contact battery feed
- Connector corrosion or pin damage at the downstream sensor
- Open thermistor element or broken heater winding inside the sensor
- Faulty sensor replacement or installation fault
- Intermittent harness damage near exhaust, mounting bracket, or flex areas
