With Manufacturer's Scan Tool

Engine Coolant Temperature (ECT) Sensor -G62-, Checking

Special tools and equipment







- VAG1526A
- VAG1594A
- VAG1598/31
- VAS5051 with VAG5051/1

Test requirements:
- Engine cold

Test sequence
- Connect VAS5051 scan tool and select the control module for engine electronics using "address word" 01. Engine must be run at idle. Connecting VAS 5051/VAG 1551 Scan Tool (ST)

Display on VAS 5051:







- Under -1- select diagnostic function "08 - Read measured value block".

Display on VAS 5051:







1 - Enter display group
- Enter "004" for "display group number 004" in field -2- and confirm entry by pressing -Q- button.

Display on VAS 5051:







- Check Engine Coolant Temperature (ECT) sensor -G62- in display field -3-.

Display Group 044:

- Exit function "08 - Read Measuring Value Block" by pressing <- button.

If display field 3 shows an implausible value:
- Disconnect Engine Coolant Temperature (ECT) sensor connector at -G2-/-G62- (arrow).







- Connect multimeter between terminals -C- and -D- of sensor to measure internal resistance.

Range A shows resistance values for temperature range from 0 to 50 degree C, and range B shows values for temperature range from 50-100 degree C.







Read-out examples:
- 30 degree C corresponds to a resistance of 1500 to 2000 Ohm
- 80 degree C corresponds to a resistance of 275 to 375 Ohm

If specified value is not obtained:
- Replace coolant temperature sensor.

If specified value is obtained:
- Connect VAG1598/31 test box at wiring harness to ECM, do not connect ECM. Electrical Testing Using VAG1598/31 Test Box







- Check following wire connections for open circuit and short circuit to Ground (GND) and B+:

Harness connector VAG1598/31 test box
Terminal Socket
3 (signal) 93
4 108

- Check both wires to each other for short circuit.
- Repair open circuit or short circuit if necessary.

If no malfunctions are found in wires:
- Replace Engine Control Module (ECM).