With Manufacturer's Scan Tool
Engine Coolant Temperature (ECT) Sensor -G62-, Testing
Special tools and equipment
- VAG 1526A
- VAG 1594A
- VAG 1598/31
- VAS 5051 with VAS 5051/1
Test requirement:
- Engine cold
Test sequence
- Connect the vehicle diagnostic, testing and information system VAS 5051 and select the vehicle system "01 - Engine electronics" from the menu. When doing this the engine should be idling. Connecting VAS 5051/VAG1551 Scan Tool
Display on VAS 5051:
- Select the diagnosis function "08 - Read data block" from the menu -1-.
Display on VAS 5051:
1 - Enter display group
(figures up to 255)
- Using the keypad -2-, enter "004" to select Display group 004 and confirm entry with Q button.
Display on VAS 5051:
- Check display value for engine coolant temperature sensor (display zone -3-).
Display Group 004:
- Press the <- button to exit from the function "08 - Read data block".
If display zone 3 shows an implausible value:
- Unplug connector on engine coolant temperature sensor.
- Connect multimeter (resistance test range) between contacts C and D on the sender.
Scale A shows resistance values for temperature range 0 to 50 C and scale B the values for temperature range 50 to 100 C.
Examples:
- 30 degree C corresponds to a resistance from 1500 to 2000 ohms
- 80 degree C corresponds to a resistance from 275 to 375 ohms
If the specification is not attained:
- Fit a new engine coolant temperature sensor.
If the specification is obtained:
- Connect test box VAG 1598/31 to wiring harness for engine control module. Do not connect to the engine control module itself. Wiring and Component Testing Using VAG1598/31 Test Box
- Test for open circuit and short to positive or Ground in the following wiring connections:
Connector Test box VAG 1598/31
Contact Socket
3 (signal) 93
4 108
- Test for short circuits between the two wires.
- Correct any open/short circuit as necessary.
If no fault is detected:
- Fit a new engine control module. With Manufacturer's Scan Tool