Pinpoint Test D: DTC C1885
Vehicle Dynamic Suspension
Pinpoint Tests
Pinpoint Test D: DTC C1885
Refer to Wiring Diagram Set 41, Vehicle Dynamic Suspension for schematic and connector information. Diagrams By Number
Normal Operation
The Vehicle Dynamics Module (VDM) sends power to the height sensor along circuit 417 (VT/OG) and the voltage returns along circuit 432 (BK/PK). The sensor sends the position signal back to the VDM along circuit 427 (PK/BK).
- DTC C1885 (Air Suspension RR Height Sensor Circuit Failure) - With the ignition in the RUN position, if the height sensor is reading less than 0.5 volt or more than 4.5 volts, DTC C1885 will be set.
This pinpoint test is intended to diagnose the following:
- Wiring, terminals or connectors
- Air suspension height sensor
- VDM
PINPOINT TEST D: DTC C1885
NOTICE: Use the Flex Probe Kit for all test connections to prevent damage to the wiring terminals. Do not use standard multi-meter probes.
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D1 CHECK THE HEIGHT SENSOR (RR_HEIGHT) PID
- Turn the air suspension switch to the OFF position.
- Disconnect the lower end of the air suspension height sensor link.
- Connect the scan tool.
- Ignition ON.
- Enter the following diagnostic mode on the scan tool: DataLogger - VDM.
- Monitor the RR_HEIGHT PID while slowly moving the air suspension height sensor through its full range of motion.
- Does the height sensor PID display vary from 0.5 volt to 4.5 volts?
Yes
An intermittent fault condition is indicated. INSPECT the height sensor electrical connector for corrosion and damage. REPAIR as necessary. CLEAR the DTCs. REPEAT the self-test.
No
CONNECT the lower end of the height sensor link. GO to D2.
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D2 CHECK THE HEIGHT SENSOR CIRCUITS FOR A SHORT TO VOLTAGE
- Ignition OFF.
- Disconnect: VDM C2131b.
- Disconnect: Air Suspension Height Sensor C4043.
- Ignition ON.
- Measure the voltage between ground and:
- air suspension height sensor C4043-3, circuit 417 (VT/OG), harness side.
- air suspension height sensor C4043-2, circuit 427 (PK/BK), harness side.
- air suspension height sensor C4043-1, circuit 432 (BK/PK), harness side.
- Is any voltage present?
Yes
REPAIR the affected circuit(s). CLEAR the DTCs. REPEAT the self-test.
No
GO to D3.
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D3 CHECK THE HEIGHT SENSOR CIRCUITS FOR A SHORT TO GROUND
- Ignition OFF.
- Measure the resistance between ground and:
- air suspension height sensor C4043-3, circuit 417 (VT/OG), harness side.
- air suspension height sensor C4043-2, circuit 427 (PK/BK), harness side.
- air suspension height sensor C4043-1, circuit 432 (BK/PK), harness side.
- Are the resistances greater than 10,000 ohms?
Yes
GO to D4.
No
REPAIR the affected circuit(s). CLEAR the DTCs. REPEAT the self-test.
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D4 CHECK THE RIDE HEIGHT SENSOR CIRCUITS FOR AN OPEN
- Measure the resistance between VDM C2131b, harness side and air suspension height sensor C4043, harness side as indicated in the following chart:
- Are the resistances less than 5 ohms?
Yes
GO to D5.
No
REPAIR the affected circuit(s). REPEAT the self-test.
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D5 CHECK THE RIDE HEIGHT SENSOR CIRCUITS FOR A SHORT TOGETHER
- Measure the resistance between the ride height sensor circuits, harness side, as indicated in the following chart:
- Are the resistances greater than 10,000 ohms?
Yes
GO to D6.
No
REPAIR the affected circuit(s). CLEAR the DTCs. REPEAT the self-test.
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D6 CHECK THE HEIGHT SENSOR OUTPUT VOLTAGE
- Connect: VDM C2131b.
- Connect a fused jumper wire between C4043-3, circuit 417 (VT/OG), harness side and pin 3, circuit 417 (VT/OG), component side.
- Connect a fused jumper wire between C4043-1, circuit 432 (BK/PK), harness side and pin 1, circuit 432 (BK/PK), component side.
- Ignition ON.
- Measure the voltage C4043-2, circuit 427 (PK/BK), harness side and ground, while slowly moving the air suspension height sensor through its full range of motion.
- Does the voltage vary from 0.5 volt to 4.5 volts?
Yes
CONNECT the lower end of the height sensor link. GO to D7.
No
INSTALL a new height sensor. CLEAR the DTCs. REPEAT the self-test.
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D7 VERIFY VDM CONNECTIONS
- Ignition OFF.
- Disconnect: VDM C2131b and C2131a.
- Check VDM connectors C2131a and C2131b for:
- corrosion
- spread terminals
- pushed-out pins
- Connect: VDM C2131b and C2131a.
- Make sure the connectors seat correctly, then operate the system and verify the concern is still present.
- Is the concern still present?
Yes
INSTALL a new VDM. REFER to Vehicle Dynamics Module (VDM) Service and Repair.
No
The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. CLEAR the DTCs. REPEAT the self-test.
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