Pinpoint Test AA: The Message Center Is Not Operating Correctly
Instrumentation, Message Center and Warning Chimes
Pinpoint Tests
Pinpoint Test AA: The Message Center Is Not Operating Correctly
Refer to Wiring Diagram Set 60, Instrument Cluster (IC) for schematic and connector information. Diagrams By Number
Normal Operation
The message center uses the Instrument Cluster (IC) RUN/START, keep alive B+ voltage and ground circuits. The message center functionality is controlled through the message center switch, which is hardwired to the IC through input and return circuits.
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 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 if the IC detects a message center button pressed for more than 2 minutes and on-demand during a self-test.
- DTC B1206 (EIC Switch-1 Assembly Circuit Open) - a continuous and on-demand DTC that sets in the IC if the IC detects an open on the message center switch input and return circuits.
- DTC B1208 (EIC Switch-1 Assembly Circuit Short to Ground) - a continuous and on-demand DTC that sets in the IC if the IC detects a short to ground on the message center input circuit.
This pinpoint test is intended to diagnose the following:
- Wiring, terminals or connectors
- Message center switch
- IC
PINPOINT TEST AA: 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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AA1 RETRIEVE THE RECORDED DTCs FROM THE IC SELF-TEST
- Check for recorded DTCs from the IC self-test.
- Are any DTCs recorded?
Yes
GO to AA4.
No
GO to AA2.
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AA2 CHECK THE IC PID FOR THE MESSAGE CENTER
- Ignition ON.
- Enter the following diagnostic mode on the scan tool: IC DataLogger .
- Select the IC message center switch PIDs (INFOSW, SETUPSW and RES_SW). Monitor the PIDs while pressing each message center switch (INFO, SETUP and RESET).
- Do the PIDs agree with the switch position?
Yes
GO to AA3.
No
INSTALL a new IC. REFER to Instrument Cluster (IC) Instrument Cluster (IC). TEST the system for normal operation.
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AA3 CARRY OUT THE IC DEALER TEST MODE
- NOTE: The all segments display is the second button press after entering the dealer test mode immediately following the gauge test.
- Enter the IC dealer test mode. Scroll through the displays until the message center displays all the segments.
- Does the message center display all the display segments?
Yes
The message center is operating correctly. If the concern is related to a specific message, REFER to Symptom Chart - Information And Message Center.
No
INSTALL a new IC. REFER to Instrument Cluster (IC) Instrument Cluster (IC). TEST the system for normal operation.
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AA4 CHECK FOR VOLTAGE FROM THE IC
- Ignition OFF.
- Disconnect: Message Center Switch C269 .
- Ignition ON.
- Measure the voltage between the message center switch C269-5, circuit CMC29 (GN/VT), harness side and the message center switch C269-4, circuit RMC27 (WH/BN), harness side.
- Is the voltage approximately 5 volts or greater?
Yes
INSTALL a new message center switch. REFER to Message Center Switch Removal and Replacement. TEST the system for normal operation.
No
GO to AA5.
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AA5 CHECK THE MESSAGE CENTER SIGNAL AND RETURN CIRCUITS FOR A SHORT TO VOLTAGE
- Disconnect: IC C220 .
- Ignition ON.
- Measure the voltage between the IC C220-16, circuit CMC29 (GN/VT), harness side and ground; and between the IC C220-3, circuit RMC27 (WH/BN), harness side and ground.
- Is any voltage present?
Yes
REPAIR the circuit in question for a short to voltage. CLEAR the DTCs. REPEAT the self-test.
No
GO to AA6.
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AA6 CHECK THE MESSAGE CENTER SIGNAL CIRCUITS FOR A SHORT TO GROUND
- Ignition OFF.
- Disconnect: Message Center Switch C269 .
- Measure the resistance between the IC C220-16, circuit CMC29 (GN/VT), harness side and the message center switch C269-5, circuit CMC29 (GN/VT), harness side; and between the IC C220-16, circuit CMC29 (GN/VT), harness side and ground.
- Is the resistance less than 5 ohms between the IC and the message center switch, and greater than 10,000 ohms between the IC and ground?
Yes
GO to AA7.
No
REPAIR circuit CMC29 (GN/VT) for an open and a short to ground. CLEAR the DTCs. REPEAT the self-test.
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AA7 CHECK THE MESSAGE CENTER RETURN CIRCUIT FOR AN OPEN
- Measure the resistance between the IC C220-11, circuit RMC27 (WH/BN), harness side and the message center switch C269-4, circuit RMC27 (WH/BN), harness side.
- Is the resistance less than 5 ohms?
Yes
GO to AA8.
No
REPAIR circuit RMC29 (WH/BN) for an open. CLEAR the DTCs. REPEAT the self-test.
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AA8 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. CLEAR the DTCs. REPEAT the self-test.
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