P1570

P1570
Immobilizer - implausible operating range

P1571
Immobilizer - Interruption 1 no signal

Function
During a restart of the engine or Motronic-Reset, the ECM communicates with the immobilizer control module. The engine can be started when this communication takes place properly. If the communication is interfered with, the engine will stop after 1 second (the fuel injection is interrupted) and the immobilizer warning light blinks.

Diagnostic conditions
Condition Start
Motronic-Reset





Wiring Diagram.









Diagnostic procedure
Check signal wire for continuity
1. Remove connector for immobilizer control module.
2. Remove ECM connector.
3. Connect ohmmeter to ECM connector, pin 88 and to immobilizer control module connector, pin 9.

- Specified value: 0 - 5 ohms
- If meter reads infinite resistance, remove connector X 4/2

4. Connect ohmmeter to connector X 4/2, pin 12 on pin side and ECM connector, pin 88.

- Specified value: 0 - 5 ohms
- If meter reads infinite resistance, repair wiring harness.

5. Connect ohmmeter to connector X 4/2, pin 12 on cavity side and immobilizer control module connector, pin 9.

- Specified value: 0 - 5 ohms
- If meter reads infinite resistance, repair wiring harness.

Check signal wire for short circuit to ground.
1. Remove immobilizer control module connector.
2. Remove ECM connector.
3. Connect ohmmeter to ECM connector, pin 88 and ground.

- Specified value: infinite resistance
- If meter reads 0 - 5 ohms, check wiring for chafing and pinching damage.

Check signal wire for short circuit to B+.
1. Remove immobilizer control module connector
2. Remove ECM connector.
3. Connect voltmeter to ECM connector, pin 88 and B+ (terminal 30).

- Specified value: 0 Volt
- If meter reads battery voltage, check wiring for chafing or pinching damage.