Control Module Wires, Checking
-- Connect test box (VAG1598/42) to Engine Control Module (ECM) -J623- wiring harness using adapter cable (VAG1598/39-1), connecting test box for wiring test.
-- Disconnect 2-pin connector -1- from Engine Coolant Temperature (ECT) Sensor -G62-.
-- Check wires between test box and 2-pin connector for open circuit according to wiring diagram.
Terminal 1+socket 52
Terminal 2+socket 53
Wire resistance: max. 1.5Ω
-- Also check wires for short circuit to each other, to vehicle Ground (GND) and to B+.
Specified value: ∞ Ω
If no malfunctions are found in wires:
-- Measure resistance between terminals on sensor.
See diagram for specified value
Range A displays resistance values for the temperature range of 0 to 50°C, range B displays resistance values for the temperature range of 50 to 100°C.
Read-out examples:
- 30 °C corresponds to a resistance of 1500 to 2000 Ω
- 80 °C corresponds to a resistance of 275 to 375Ω
If specified value is not obtained:
-- Replace Engine Coolant Temperature (ECT) Sensor -G62-.
- The cooling system is under pressure.
- Danger of scalding when opening!
-- Erase DTC memory of Engine Control Module (ECM) DIAGNOSTIC MODE 04 - ERASE DTC MEMORY .
-- Generate readiness code READINESS CODE .
If no malfunctions are detected in the wires and the resistance values are OK:
-- Replace Engine Control Module (ECM) -J623- ENGINE CONTROL MODULES, REPLACING .