How to Troubleshoot the Gauges
The gauge control module (TACH) has a self-diagnostic function shown, and also has a customize reset function.
- The beeper drive circuit check.
- The indicator drive circuit check.
- The switch input test.
- The LCD segments check.
- The gauges drive circuit check (Tachometer, Fuel gauge, Coolant temperature gauge).
- The communication line check (of the body-controller area network (B-CAN) communication line and the fast-controller area network (F-CAN) communication line between the gauges).
- The UART line check between the gauge control module (TACH) and the gauge control module (SPEEDO).
NOTE: Indicators are also controlled via the communication line.
Entering the self-diagnostic function
Before doing the self-diagnostic function, check the No. 10 (7.5 A) fuse in the under-dash fuse/relay box and No. 16 (15 A) fuse in the under-hood fuse/relay box.
| 1. | Push and hold the SEL/RESET switch button.
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| 2. | Turn the headlights ON.
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| 3. | Turn the ignition switch ON (II).
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| 4. | Within 5 sec., turn the headlights OFF, then ON and OFF again.
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| 5. | Within 5 sec., release the SEL/RESET switch button, and then push and release the button three times repeatedly.
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NOTE:
- While in the self-diagnostic mode, the dash lights brightness controller operates normally.
- While in the self-diagnostic mode, the SEL/RESET button is used to start the Beeper Drive Circuit Test and the Gauge Drive Circuit Check.
- If the vehicle speed exceeds 2 km/h (1.2 mph) or the ignition switch is turned OFF, the self-diagnostic mode ends.
The Indicator Drive Circuit Check
When entering the self-diagnostic mode, the following indicators blink:
ABS indicator, brake system indicator, charging system indicator, cruise control indicator, cruise indicator, EPS indicator, high beam indicator, immobilizer indicator, lights-on indicator, low fuel indicator, malfunction indicator lamp (MIL), oil pressure indicator, seat belt indicators, security indicator, SRS indicator, VSA indicator, VSA activation indicator, front fog light indicator, rear fog light indicator, master warning indicator, REV indicator, ECO indicator.
Switch Input Check
After the intermittent beeper sounds at the initial stage of the self-diagnostic, a beeper sounds continuously while any of the following switch inputs are switched from OFF to ON:
Cruise control master, SET, RESUME, CANCEL switches, SEL/RESET switch, illumination volume (+), (-) switch, brake fluid level switch, parking brake switch, and VSA OFF switch.
The Beeper Drive Circuit Check
When entering the self-diagnostic mode, the beeper sounds five times.
The LCD Segment Check
When entering the self-diagnostic mode, the LCD display indicates ‘‘· · ·''. The indicated object blinks five times.
The Gauge Drive Circuit Check
When entering the self-diagnostic mode, the tachometer needle sweeps from the minimum position to maximum position, then returns to the minimum position.
NOTE:
After the beeper stops sounding and the gauge needle returns to the minimum position, pushing the SEL/RESET switch starts the Beeper Drive Circuit Check (one beep) and the Gauge Drive Circuit Check again.
The check cannot be started again until the gauge needle returns to the minimum position.
If the needle fails to sweep, or the beeper does not sound, replace the gauge control module (tach).
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 are OK. If faulty, the word ‘‘Error'' will be indicated on the odometer display followed by number(s).
- Error 1: F-CAN communication line error
- Error 2: B-CAN communication line error
- Error 3: UART communication line error
Error Code List| Error code | Type of communication line(s) error |
|---|
| Error 1 | F-CAN communication |
| Error 2 | B-CAN communication |
| Error 3 | UART communication |
| Error 12 | F-CAN and B-CAN communication |
| Error 13 | F-CAN and UART communication |
| Error 23 | B-CAN and UART communication |
| Error 123 | F-CAN, B-CAN and UART communication |
Example Indication
- If the word ‘‘Error 1'' is indicated, there is a malfunction in the communication line between the gauge control module (tach) and the fast-controller area network (F-CAN). Check for DTCs in the ECM 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 communication line between the gauge control module (tach) and the body-controller area network (B-CAN). Go to indicated troubleshooting (B1155 to B1160).
- If the word ‘‘Error 3'' is indicated, there is a malfunction in the UART communication line between the gauge control module (tach) and the gauge control module (speedo). Go to the gauge control module (tach) input test and check the A20 terminal. If the wire harness is OK, substitute a known-good gauge control module (speedo) and recheck.
If any F-CAN or B-CAN communication line errors are found, go to DTC check using HDS.
Ending the self-diagnostic function
Turn the ignition switch OFF.
NOTE: If the vehicle speed exceeds 2 km/h (1.2 mph), the self-diagnostic function ends.