Pinpoint Test AE: The Message Center Is Not Operating Correctly
Instrumentation, Message Center and Warning Chimes
Pinpoint Test AE: The Message Center Is Not Operating Correctly
Refer to Wiring Diagram Set 60, Instrument Panel Cluster for schematic and connector information Electrical Diagrams.
Normal Operation
The Instrument Panel Cluster (IPC) receives the message center switch status from the Steering Column Control Module (SCCM) over the High Speed Controller Area Network (HS-CAN). The message center functionality is controlled through the message center switch (part of the LH steering wheel switch), which is hardwired to the Steering Column Control Module (SCCM) through input and return circuits. The message center switch portion of the LH steering wheel switch is comprised of 5 buttons. Each button operates a unique switch within the message center switch portion of the LH steering wheel switch assembly using a different resistance value associated with each specific button. The SCCM (Steering Column Control Module) sends out a reference voltage to the LH steering wheel switch on the input circuit and monitors the voltage drop when a message center switch button is pressed. The voltage drop varies depending upon the resistance of the specific button pressed, providing indication to the SCCM (Steering Column Control Module), which switch is pressed.
SCCM (Steering Column Control Module) DTCs
This pinpoint test is intended to diagnose the following:
- Wiring, terminals or connectors
- Clockspring
- Message center switch (part of the LH steering wheel switch)
- SCCM (Steering Column Control Module)
- IPC (Instrument Panel Cluster)
PINPOINT TEST AE : THE MESSAGE CENTER IS NOT OPERATING CORRECTLY
NOTICE: Use the correct probe adapter(s) when making measurements. Failure to use the correct probe adapter(s) may damage the connector.
AE1 RETRIEVE THE RECORDED DTCs FROM THE IPC (Instrument Panel Cluster) SELF-TEST
- Check for recorded IPC (Instrument Panel Cluster) DTCs from the continuous self-test.
Is DTC U0212:00 recorded?
Yes
GO to Pinpoint Test AY Pinpoint Test AY: DTC U0212:00.
No
GO to AE2.
AE2 RETRIEVE THE RECORDED DTCs FROM THE SCCM (Steering Column Control Module) SELF-TEST
- Retrieve the recorded SCCM (Steering Column Control Module) DTCs from the self-test.
Are any DTCs recorded?
Yes
For DTC B137F:09, INSTALL a new LH steering wheel switch. CLEAR the DTC. REPEAT the self-test.
For DTC B137F:11 or DTC B137F:17, GO to AE3.
For all other DTCs, REFER to DTC Charts Instrumentation, Message Center and Warning Chimes.
No
GO to AE3.
AE3 CHECK THE IPC (Instrument Panel Cluster) OUTPUT AT THE LH STEERING WHEEL SWITCH
- Ignition OFF.
- Disconnect: LH Steering Wheel Switch C2998.
- Ignition ON.
- Measure the voltage between the LH steering wheel switch C2998-1, message center return circuit (LB/BK), harness side and the LH steering wheel switch C2998-3, message center signal circuit (RD), harness side.
Is the voltage approximately 5 volts?
Yes
INSTALL a new LH steering wheel switch. CLEAR the DTCs. REPEAT the self-test.
No
GO to AE4.
AE4 CHECK THE MESSAGE CENTER SWITCH SIGNAL CIRCUIT BETWEEN THE LH STEERING WHEEL SWITCH AND THE UPPER CLOCKSPRING FOR AN OPEN AND A SHORT TO GROUND
- Ignition OFF.
- Remove the driver air bag.
- Disconnect: Upper Clockspring C218B.
- Measure the resistance between the LH steering wheel switch C2998-3, message center signal circuit (RD), harness side and the upper clockspring C218B-14, message center signal circuit (RD), harness side; and between the LH steering wheel switch C2998-3, message center signal circuit (RD), harness side and ground.
Is the resistance less than 5 ohms between the LH steering wheel switch and the clockspring, and greater than 10,000 ohms between the LH steering wheel switch and ground?
Yes
GO to AE5.
No
REPAIR the steering wheel harness message center signal circuit (RD) for an open or short to ground. CLEAR the DTC. REPEAT the self-test.
AE5 CHECK THE MESSAGE CENTER SWITCH RETURN CIRCUIT BETWEEN THE LH STEERING WHEEL SWITCH AND THE UPPER CLOCKSPRING FOR AN OPEN
- Measure the resistance between the LH steering wheel switch C2998-1, message center return circuit (LB/BK), harness side and the upper clockspring C218B-8, LH steering wheel return circuit (LB/BK), harness side.
Is the resistance less than 5 ohms?
Yes
GO to AE6.
No
REPAIR the steering wheel harness message center return circuit (LB/BK) for an open. CLEAR the DTC. REPEAT the self-test.
AE6 CHECK THE MESSAGE CENTER SWITCH SIGNAL CIRCUIT IN THE CLOCKSPRING FOR AN OPEN
- Measure the resistance between the upper clockspring C218b pin 14, component side and the lower clockspring C218c pin 6, component side.
Is the resistance less than 5 ohms?
Yes
GO to AE7.
No
INSTALL a new clockspring. CLEAR the DTCs. REPEAT the self-test.
AE7 CHECK THE MESSAGE CENTER SWITCH RETURN CIRCUIT IN THE CLOCKSPRING FOR AN OPEN
- Measure the resistance between the upper clockspring C218b pin 8, component side and the lower clockspring C218c pin 9, component side.
Is the resistance less than 5 ohms?
Yes
GO to AE8.
No
INSTALL a new clockspring. CLEAR the DTCs. REPEAT the self-test.
AE8 CHECK FOR CORRECT SCCM (Steering Column Control Module) OPERATION
- Disconnect the SCCM (Steering Column Control Module) connector.
- Check for:
- corrosion
- damaged pins
- pushed-out pins
- Connect the SCCM (Steering Column Control Module) connector and make sure it seats correctly.
- Operate the system and verify the concern is still present.
Is the concern still present?
Yes
INSTALL a new SCCM (Steering Column Control Module). TEST the system for normal operation.
No
The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector.