Pinpoint Tests AL: The Message Center Does Not Operate Correctly
Instrumentation, Message Center and Warning Chimes
Pinpoint Tests
Pinpoint Test AL: The Message Center Does Not Operate Correctly
Refer to Wiring Diagrams 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 VMC29 (YE). 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) - sets in continuous memory when the IC detects any message center switch stuck for greater than 2 minutes and on-demand when the IC detects any message center button stuck during the self-test.
- DTC B1206 (EIC Switch-1 Assembly Circuit Open) - a continuous and on-demand DTC that sets when the IC detects an open on the message center switch input, circuit CMC29 (GN/VT).
- DTC B1208 (EIC Switch-1 Assembly Circuit Short to Ground) - a continuous and on-demand DTC that sets when the IC detects a short to ground on the message center switch input, circuit CMC29 (GN/VT).
This pinpoint test is intended to diagnose the following:
- Wiring, terminals or connectors
- Message center switch
- IC
PINPOINT TEST AL: THE MESSAGE CENTER DOES NOT OPERATE CORRECTLY
NOTICE: Use the correct probe adapter(s) when making measurements. Failure to use the correct probe adapter(s) may damage the connector.
-------------------------------------------------
AL1 RETRIEVE THE RECORDED DTCs FROM THE IC SELF-TEST
- Retrieve the recorded IC DTCs from the self-test.
- Are any DTCs recorded?
Yes
For DTC B1205, INSTALL a new message center switch. REFER to Message Center Switch Service and Repair. TEST the system for normal operation.
For DTC B1206 or B1208, GO to AL3.
For all other DTCs, REFER to DTC Charts. Instrumentation, Message Center and Warning Chimes
No
GO to AL2.
-------------------------------------------------
AL2 CHECK THE IC ODOMETER OPERATION
- Ignition ON.
- Observe the odometer display in the message center.
- Is the odometer displayed?
Yes
GO to AL6.
No
If the display is blank, PRESS the INFO button to see if the message center was previously set to the blank display. If the display remains blank, INSTALL a new IC. REFER to Instrument Cluster (IC) Instrument Cluster (IC). TEST the system for normal operation.
-------------------------------------------------
AL3 CHECK CIRCUITS CMC29 (GN/VT) AND RMC27 (WH/BN) FOR A SHORT TO VOLTAGE
- Disconnect: IC C220.
- Ignition ON.
- Measure the voltage between the IC C220-24, circuit CMC29 (GN/VT), harness side and ground; and between the IC C220-11, circuit RMC27 (WH/BN), harness side and ground.
- Is any voltage present?
Yes
REPAIR the circuit in question. CLEAR the DTCs. REPEAT the self-test.
No
GO to AL4.
-------------------------------------------------
AL4 CHECK CIRCUIT CMC29 (GN/VT) FOR AN OPEN AND A SHORT TO GROUND
- Ignition OFF.
- Disconnect: Message Center Switch C269.
- Measure the resistance between the IC C220-24, circuit CMC29 (GN/VT), harness side and the message center switch C269-3, circuit CMC29 (GN/VT), harness side; and between the IC C220-24, 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 AL5.
No
REPAIR the circuit. CLEAR the DTCs. REPEAT the self-test.
-------------------------------------------------
AL5 CHECK CIRCUIT RMC27 (WH/BN) FOR AN OPEN
- Measure the resistance between the IC C220-11, circuit RMC27 (WH/BN), harness side and the message center switch C269-2, circuit RMC27 (WH/BN), harness side.
- Is the resistance less than 5 ohms?
Yes
GO to AL6.
No
REPAIR the circuit. CLEAR the DTCs. REPEAT the self-test.
-------------------------------------------------
AL6 CHECK FOR VOLTAGE FROM THE IC
- Connect: IC C220.
- Ignition ON.
- Measure the voltage between the message center switch C269-3, circuit CMC29 (GN/VT), harness side and the message center switch C269-2, circuit VMC29 (YE), harness side.
- Is the voltage greater than 10 volts?
Yes
INSTALL a new message center switch. REFER to Message Center Switch Service and Repair. TEST the system for normal operation.
No
GO to AL7.
-------------------------------------------------
AL7 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.
-------------------------------------------------