Initial Inspection and Diagnostic Overview

Self-diagnostic Function

The gauge control module has a self-diagnostic function that checks these circuits:
- The beeper drive circuit.
- The indicator drive circuit.
- The LCD segments.
- The gauges drive circuit (Speedometer, Tachometer, Fuel gauge, Coolant temperature gauge).
- The communication line (the coolant temperature signal and vehicle speed signal line between the gauge and the ECM/PCM).

Entering the self-diagnostic function

Before entering the self-diagnostic function, check the No. 9 (10 A) fuse in the under-hood fuse/relay box and the No. 10 (7.5 A) fuse in the under-dash fuse/relay box.

1. Press and hold the TRIP/RESET button.
2. Turn the headlights ON.
3. Turn the ignition switch ON (II).
4. Within 5 sec, turn the headlights OFF, then ON and OFF again.




5. Within the next 5 sec, release the TRIP/RESET button, then press and release the button three times.

NOTE:
- While in the self-diagnostic function, the dash lights brightness controller does not operate.
- While in the self-diagnostic function, the TRIP/RESET button is used to start the Beeper Drive Circuit Test and the Gauge Drive Circuit Check.
- If the vehicle speed exceeds 1.2 mph (2 km/h) or the ignition switch is turned OFF, the self-diagnostic function ends.

The Beeper Drive Circuit Check

When entering the self-diagnostic function, the beeper sounds five times.

The Indicator Drive Circuit Check

When entering the self-diagnostic function, these indicator lights blink:
Seat belt reminder light. Door indicator. Brake system light. Charging system light. Cruise indicator. Low engine oil pressure indicator. Low fuel indicator. Maintenance required indicator. Washer fluid level indicator (Canada models), A/T gear position indicator (1, 2, D, N, R, P), Over drive off indicator (A/T) VSA indicator, VSA activation indicator, ABS indicator Lights-on indicator, Malfunction indicator lamp (MIL), Low tire pressure indicator, TPMS indicator.

Switch Input Check

After the intermittent beeper sounds at the initial stage of self-diagnostics. The beeper will continue to sound while any of the following switch inputs are switched from Off to On: Cruise control master, SET, RESUME, CANCEL switches, SEL/RESET switch, and VSA Off switch.

The LCD Segments Check

When entering the self-diagnostic function, the odo/trip meter segments blink five times.




The Gauge Drive Circuit Check

When entering the self-diagnostic function, the speedometer, the tachometer, the fuel gauge, and the coolant temperature gauge needles move from the minimum position to the maximum position, then return to the minimum position.

NOTE: After the beeper stops sounding and the gauge needles return to the minimum position, pressing the TRIP/RESET button starts the Beeper Drive Circuit Check (one beep), and the Gauge Drive Circuit Check again. The check cannot be started until the gauge needles return the minimum position.




The Communication Line Check

While in the self-diagnostic mode, the Communication Line Check starts after the LCD Segments Check. If all segments come on, the communication line is OK. If faulty, the word "Error" will be indicated on the odometer display followed by number(s).

- If the word "Error 1" is indicated, there is a malfunction in the communication line between the gauge control module and the fast-controller area network (F-CAN). Check for DTCs in the ECM/PCM and troubleshoot any DTCs found. If no DTCs are found, go to indicated troubleshooting.
- If the word "Error 2" is indicated, there is a malfunction in the UART communication line between the gauge control module and the multiplex control unit. Go to the gauge control module input test and check the No. 27 terminal. If the wire harness is OK, substitute a known-good gauge control module and recheck.
- If the word "Error 3" is indicated, there is a malfunction in the communication line between the gauge control module and F-CAN and UART. Check for DTCs in the ECM/PCM and troubleshoot any DTCs found.

Ending the self-diagnostic function

Turn the ignition switch OFF.

NOTE: If the vehicle speed exceeds 1.2 mph (2 km/h), the self-diagnostic function ends.