Temperature Gauge: Testing and Inspection
Engine Coolant Temperature (ECT) Gauge, checking/troubleshootingChecking
If Fuel and Engine Coolant Temperature Gauges simultaneously indicate false readings, check voltage stabilizer.
Leave battery and electrical connectors connected for the following tests.
• check these first:
^ verify complaint
^ battery OK
^ chassis ground OK
^ fuse OK
^ remove connector from Engine Coolant Temperature (ECT) Sensor
^ connect lead A of VW 1301 to ground
^ connect lead B of VW 1301 to wire (yellow/red) leading to Engine Coolant Temperature Gauge
^ switch ignition ON
- Engine Coolant Temperature (ECT) warning light 1 flashes for approximately 3 seconds
^ adjust VW 1301 as follows:
- Engine Coolant Temperature Gauge needle must correspond to specified values
- deviation of one needle width to the left or right is permissible
Troubleshooting
Use the following procedure to determine the cause of false Engine Coolant Temperature Gauge readings.
^ check Engine Coolant Temperature (ECT) Gauge (as outlined previously)
If Engine Coolant Temperature Gauge checked OK,
^ replace Engine Coolant Temperature Sensor
If Engine Coolant Temperature Gauge needle moves during check but is inaccurate,
^ check voltage stabilizer
- output voltage must be 9.5V-10.5V
It voltage stabilizer specified value is obtained
^ replace Engine Coolant Temperature Gauge
If voltage stabilizer specified value is not obtained
^ replace voltage stabilizer
If Engine Coolant Temperature Gauge needle does not move during check,
^ check wiring from ECT sensor to ECT gauge according to wiring diagram
If wiring checks OK,
^ check voltage stabilizer
- output voltage must be 9.5V-1 0.5V
It voltage stabilizer specified value is obtained
^ replace Engine Coolant Temperature Gauge