Pinpoint Test AI: The Message Center Is Not Operating Correctly
Instrumentation, Message Center and Warning Chimes
Pinpoint Test AI: The Message Center Is Not Operating Correctly
Refer to Wiring Diagram Set 60, Instrument Cluster for schematic and connector information [1][2]Diagrams By Number.
Normal Operation
The message center shares the Instrument Panel Cluster (IPC) RUN/START voltage, keep alive memory voltage and the IPC (Instrument Panel Cluster) logic ground to operate. The message center functionality is controlled through the message center switch and is hardwired to the IPC (Instrument Panel Cluster) through separate signal and return circuits.
There are 3 message center switch buttons with each button operating a switch that uses different resistance values. The IPC (Instrument Panel Cluster) 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 varies depending upon the resistance of each button, providing a specific indication to the IPC (Instrument Panel Cluster) which switch is pressed.
- DTC B1A82:11 (External Trip Switch: Circuit Short to Ground)- a continuous DTC that sets in the IPC (Instrument Panel Cluster) if the IPC (Instrument Panel Cluster) detects a short to ground on the message center signal circuit.
- DTC B1A82:13 (External Trip Switch: Circuit Open)- a continuous DTC that sets in the IPC (Instrument Panel Cluster) if the IPC (Instrument Panel Cluster) detects an open on the message center signal circuit.
- DTC B1A82:23 (External Trip Switch: Signal Stuck Low)- a continuous DTC that sets in the IPC (Instrument Panel Cluster) if the IPC (Instrument Panel Cluster) senses any message center button as pressed for greater then 120 seconds.
If any one of the message center switch buttons is stuck the fault recognized by the vehicle occupants is as follows:
- RESET button stuck: Upon each transition from Off/ACC to RUN/START, the message center displays ENGINEERING TEST MODE for 3 seconds.
- INFO button stuck: The message center display continuously scrolls through the INFO menu.
- SETUP button stuck: The message center display continuously scrolls through the SETUP menu.
This pinpoint test is intended to diagnose the following:
- Wiring, terminals or connectors
- Message center switch
- IPC (Instrument Panel Cluster)
PINPOINT TEST AI : 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.
AI1 RETRIEVE THE RECORDED DTCs FROM THE IPC (Instrument Panel Cluster) SELF-TEST
- Check for recorded DTCs from the IPC (Instrument Panel Cluster) self-test.
Are any DTCs recorded?
Yes
For DTC B1A82:23, INSTALL a new message center switch. REFER to Message Center Switch . TEST the system for normal operation.
For DTC B1A82:11 or DTC B1A82:13 GO to AI5.
For all other DTCs, REFER to DTC Charts Instrumentation, Message Center and Warning Chimes.
No
GO to AI2.
AI2 CHECK THE IPC (Instrument Panel Cluster) ODOMETER DISPLAY
- Ignition ON.
- Observe the odometer display in the message center.
Is the odometer displayed?
Yes
GO to AI3.
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 IPC (Instrument Panel Cluster). REFER to Instrument Panel Cluster (IPC) . TEST the system for normal operation.
AI3 CARRY OUT THE IPC (Instrument Panel Cluster) DEALER TEST MODE
- Enter the IPC (Instrument Panel Cluster) dealer test mode. Refer to IPC (Instrument Panel Cluster) Dealer Test Mode in Inspection and Verification Instrumentation, Message Center and Warning Chimes.
- NOTE: The all segments display is the second button press after entering the dealer test mode immediately following the gauge test.
Scroll through the displays until the message center displays all the segments.
Does the message center illuminate all the segments?
Yes
GO to AI4.
No
INSTALL a new IPC (Instrument Panel Cluster). REFER to Instrument Panel Cluster (IPC) . TEST the system for normal operation.
AI4 CHECK FOR VOLTAGE FROM THE IPC (Instrument Panel Cluster)
- Ignition OFF.
- Disconnect: Message Center Switch C253.
- Ignition ON.
- Measure the voltage between the message center switch C253-5, circuit CMC29 (GN/VT), harness side and the message center switch C253-4, circuit RMC27 (WH/BN), harness side.
Is the voltage approximately 5 volts?
Yes
INSTALL a new message center switch. REFER to Message Center Switch . TEST the system for normal operation.
No
GO to AI11.
AI5 CHECK THE MESSAGE CENTER SIGNAL AND RETURN CIRCUITS FOR A SHORT TO VOLTAGE
- Ignition OFF.
- Disconnect: IPC (Instrument Panel Cluster) C220.
- Ignition ON.
- Measure the voltage between the IPC (Instrument Panel Cluster) C220-6, circuit CMC29 (GN/VT), harness side and ground; and between the IPC (Instrument Panel Cluster) C220-4, 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 AI6.
AI6 CHECK THE MESSAGE CENTER SIGNAL AND RETURN CIRCUITS FOR A SHORT TO GROUND
- Ignition OFF.
- Disconnect: Message Center Switch C253.
- Measure the resistance between the IPC (Instrument Panel Cluster) C220-6, circuit CMC29 (GN/VT), harness side and ground; and between the IPC (Instrument Panel Cluster) C220-4, circuit RMC27 (WH/BN), harness side and ground.
Is the resistance greater than 10,000 ohms?
Yes
GO to AI7.
No
REPAIR the circuit in question. CLEAR the DTCs. REPEAT the self-test.
AI7 CHECK THE MESSAGE CENTER SIGNAL AND RETURN CIRCUITS FOR A SHORT TOGETHER
- Measure the resistance between the IPC (Instrument Panel Cluster) C220-6, circuit CMC29 (GN/VT), harness side; and between the IPC (Instrument Panel Cluster) C220-4, circuit RMC27 (WH/BN), harness side.
Is the resistance greater than 10,000 ohms?
Yes
GO to AI8.
No
REPAIR the circuit. CLEAR the DTCs. REPEAT the self-test.
AI8 CHECK THE MESSAGE CENTER SIGNAL CIRCUIT FOR AN OPEN
- Measure the resistance between the IPC (Instrument Panel Cluster) C220-6, circuit CMC29 (GN/VT), harness side and the message center switch C253-5, circuit CMC29 (GN/VT), harness side.
Is the resistances less than 5 ohms?
Yes
GO to AI9.
No
REPAIR the circuit. CLEAR the DTCs. REPEAT the self-test.
AI9 CHECK THE MESSAGE CENTER RETURN CIRCUIT FOR AN OPEN
- Measure the resistance between the IPC (Instrument Panel Cluster) C220-4, circuit RMC27 (WH/BN), harness side and the message center switch C253-4, circuit RMC27 (WH/BN), harness side.
Is the resistance less than 5 ohms?
Yes
GO to AI10.
No
REPAIR the circuit. CLEAR the DTCs. REPEAT the self-test.
AI10 CHECK FOR THE MESSAGE CENTER SWITCH OPERATION
- Connect: Message Center Switch C253.
- Measure the resistance between the IPC (Instrument Panel Cluster) C220-6, circuit CMC29 (GN/VT), harness side and the IPC (Instrument Panel Cluster) C220-4, circuit RMC27 (WH/BN), harness side while pressing the message center buttons according to the following table.
Message Center Button Resistance No button press 7,200-7,800 ohms INFO 123-133 ohms SETUP 1,381-1,496 ohms RESET 599-649 ohms
Is the resistance within the specifications for all positions?
Yes
GO to AI11.
No
INSTALL a new IPC (Instrument Panel Cluster). REFER to Instrument Panel Cluster (IPC) . TEST the system for normal operation.
AI11 CHECK FOR CORRECT IPC (Instrument Panel Cluster) OPERATION
- Disconnect the IPC (Instrument Panel Cluster) connector.
- Check for:
- corrosion
- damaged pins
- pushed-out pins
- Connect the IPC (Instrument Panel Cluster) 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 IPC (Instrument Panel Cluster). REFER to Instrument Panel Cluster (IPC) . 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.