Engine Temp. Gauge Inoperative

Use this fault-tracing procedure if other gauges on instrument panel are working.

Sources of Fault:





- Signal lead short-circuited to battery supply.
- Signal lead short-circuited to ground.
- Open-circuit in signal lead.
- Fault in engine management system.

Start fault-tracing at step 1, below.





1) Checking DTCs in Engine Management System:
- Ignition on.
- Read off engine management system DTCs, DLC A2. Only DTC 1-2-3 affects engine temperature: if other DTCs occur, see appropriate engine management system service manuals for fault-tracing.

If DTC 1-2-3 is posted:
- Fault in engine management system. See appropriate ALLDATA Powertrain Management Section for fault-tracing procedures.

If DTC 1-2-3 is not posted:
- Check signal lead to instrument panel. See step 2, below.

2) Checking Signal Lead to Instrument Panel:





- Ignition off.
- Expose instrument panel. (Remove Dash Board Cover) Service and Repair
- Undo instrument panel connector.
- Connect test box to cable harness connector and check ground points. Connecting Test Box





- Connect test box between instrument panel and cable harness connectors.





- Ignition on.
- Connect a voltmeter between # 26 (# A26) and # 15 (# A15) on test box.
- Voltmeter should read approx. 5.5 V.

If reading is correct:
- Instrument panel connector A not connecting properly. Check connector for loose contacts, contact resistance and oxidization. Checking Cables and Terminals
- If engine temperature gauge does not work after checking connector, replace engine temperature gauge. Service and Repair (Individual Component Replacement)

If voltmeter reads 0 V:
- Open-circuit or short-circuit to ground in signal lead between engine management connector terminal # B23 and instrument panel terminal # A26. Check lead and connections for open-circuit and short-circuit to ground.
- In cars with ECC, also check signal lead between ECC control module terminal # A23 and instrument panel terminal # A26 for open-circuit and short-circuit to ground.
- To perform above stated checks, Checking Cables and Terminals

If voltmeter reading equals battery voltage:
- Short-circuit to battery supply in signal lead between engine management system connector terminal # B23 and instrument panel terminal # A26. Check lead and connections for short-circuit to battery supply.
- In cars with ECC, also check signal lead between ECC control module terminal # A23 and instrument panel terminal # A26 for short-circuit to battery supply.
- To perform above stated checks, Checking Cables and Terminals