Pinpoint Tests AM: The Message Center Is Not Operating Correctly
Instrumentation, Message Center and Warning Chimes
Pinpoint Tests
Pinpoint Test AM: The Message Center Is Not Operating Correctly
Refer to Wiring Diagram Set 60, Instrument Cluster for schematic and connector information. Diagrams By Number
Normal Operation
The message center functionality is controlled through the message center switch, which is hardwired to the Instrument Cluster (IC) through input circuit CMC29 (GN/VT) and return circuit RMC27 (WH/BN). There are 3 message center switch buttons with each button operating a switch that uses different resistance values. The IC sends out a reference voltage to the message center switch on the input circuit and monitors the voltage drop when a message center switch button is pressed. The voltage drop will vary depending upon the resistance of each button, providing a specific indication to the IC which switch is pressed.
- DTC B1205 (EIC Switch-1 Assembly Circuit Failure) - a continuous and on-demand DTC that sets in the IC when the IC detects any of the message center switch buttons stuck closed for more than 120 seconds continuously or during the on-demand self-test.
This pinpoint test is intended to diagnose the following:
- Wiring, terminals or connectors
- Message center switch (part of the steering wheel audio control)
- IC
PINPOINT TEST AM: 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.
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AM1 RETRIEVE THE RECORDED DTCs FROM BOTH THE CONTINUOUS AND ON-DEMAND IC SELF-TESTS
- Retrieve the recorded IC DTCs from both the continuous and on-demand self-tests.
- Is DTC B1205 recorded?
Yes
CLEAR the DTCs. REPEAT the self-test. If DTC B1205 returns, INSTALL a new steering wheel control switch. CLEAR the DTCs. REPEAT the self-test.
No
GO to AM2.
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AM2 CHECK THE MESSAGE CENTER DISPLAY OPERATION USING THE SCAN TOOL
- Ignition ON.
- Enter the following diagnostic mode on the scan tool: IC DataLogger.
- Select the IC display segment control (ALL_SEG) active command. Command the display segments on. Observe the message center display.
- Does the message center display illuminate all segments?
Yes
GO to AM3.
No
GO to AM10.
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AM3 CHECK FOR THE DOOR AJAR MESSAGE
- Ignition OFF.
- Close all doors, liftgate, liftgate glass or trunk.
- Ignition ON.
- Open the LH front door while monitoring the message center display.
- Does the message center display DRIVER DOOR AJAR?
Yes
GO to AM4.
No
GO to AM10.
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AM4 CHECK FOR VOLTAGE FROM THE IC
- Ignition OFF.
- Disconnect: Clockspring C218a.
- Ignition ON.
- Measure the voltage between the clockspring C218a-7, circuit CMC29 (GN/VT), harness side and the clockspring C218a-12, circuit RMC27 (WH/BN), harness side and ground.
- Is the voltage greater than 10 volts?
Yes
GO to AM7.
No
GO to AM5.
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AM5 CHECK CIRCUIT CMC29 (GN/VT) FOR AN OPEN AND SHORT TO GROUND
- Ignition OFF.
- Disconnect: IC C220.
- Measure the resistance between the IC C220-19, circuit CMC29 (GN/VT), harness side and the clockspring C218a-7, circuit CMC29 (GN/VT), harness side; and between the IC C220-19, circuit CMC29 (GN/VT), harness side and ground.
- Is the resistance less than 5 ohms between the IC and the clockspring, and greater than 10,000 ohms between the IC and ground?
Yes
GO to AM6.
No
REPAIR the circuit. CLEAR the DTCs. REPEAT the self-test.
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AM6 CHECK CIRCUIT RMC27 (WH/BN) FOR AN OPEN
- Measure the resistance between the IC C220-22, circuit RMC27 (WH/BN), harness side and the clockspring C218a-12, circuit RMC27 (WH/BN), harness side.
- Is the resistance less than 5 ohms?
Yes
GO to AM10.
No
REPAIR the circuit. CLEAR the DTCs. REPEAT the self-test.
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AM7 CHECK CIRCUIT CMC29 (GN/VT) FOR A SHORT TO VOLTAGE
- Ignition OFF.
- Disconnect: IC C220.
- Ignition ON.
- Measure the voltage between the clockspring C218a-7, circuit CMC29 (GN/VT), harness side and ground.
- Is any voltage present?
Yes
REPAIR the circuit. TEST the system for normal operation.
No
GO to AM8.
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AM8 CHECK THE MESSAGE CENTER SWITCHES
- Ignition OFF.
- Remove the driver air bag module.
- Disconnect: Upper Clockspring Connector.
- Measure the resistance between the upper clockspring C218b pin 2, jumper harness side, and the upper clockspring C218b pin 11, jumper harness side while pressing the message center switches as follows:
- Are the resistance values within the specifications?
Yes
INSTALL a new clockspring. INSTALL the driver air bag module. CLEAR the DTCs. REPEAT the self-test.
No
GO to AM9.
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AM9 CHECK STEERING WHEEL CONTROL SWITCH HARNESS
- Check the steering wheel control switch harness for opens or shorts.
- Is the steering wheel control switch harness OK?
Yes
INSTALL a new message center switch assembly. INSTALL the driver air bag module. CLEAR the DTCs. REPEAT the self-test.
No
REPAIR or INSTALL a new steering wheel control switch harness. INSTALL the driver air bag module. CLEAR the DTCs. REPEAT the self-test.
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AM10 CHECK FOR CORRECT IC OPERATION
- Disconnect the IC connector.
- Check for:
- corrosion
- damaged pins
- pushed-out pins
- Connect the IC 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 IC. REFER to Instrument Cluster (IC) Instrument Cluster (IC). 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.
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