Motronic ECM Power Supply Relay -J271, Checking

Motronic Engine Control Module (ECM) power supply relay -J271-, checking

NOTE: The Motronic Engine Control Module (ECM) power supply relay -J271- is located in a triple relay carrier in electronic box in plenum chamber, relay position 3.
Check actuation of ECM power supply relay







- Switch ignition off.
- Remove Motronic Engine Control Module (ECM) power supply relay - J271- from triple relay carrier.
- Connect test box VAG 1598/31 to wiring harness for engine control module; do not connect engine control module. Connecting VAG 1598/31 Test Box
- Check following wiring for an open circuit or short circuit

Test box V.A.G
1598/31, socket Power supply relay, contact
23 4

Wire resistance: max. 1.5 Ohm
- Correct any open/short circuit as necessary.

If no wiring malfunction is detected:
- Check power supply for power supply relay.

Check the power supply

- Switch ignition off.
- Connect hand-held multimeter to contact 2 and 9 of relay socket and Ground to measure voltage.
Specified value: approx. battery voltage

If the specified value is not achieved, test the supply voltage according to the wiring diagram.

If the specified value is achieved, check the wiring connections between power supply relay and engine control module.

Checking wiring between power supply relay and engine control module

- Check fuse

If no malfunction is detected at the fuse.
- Check following wiring for an open circuit or short circuit

Test box V.A.G
1598/31, socket Power supply relay, contact
3

Wire resistance: max. 1.5 Ohm

- Correct any open/short circuit as necessary.

If no malfunctions have been found in any of the above checks, replace Motronic Engine Control Module (ECM) power supply relay -J271-