B1605

Symptom: Anti-theft alarm completely unserviceable. Indefinable (different functions may be affected, due to an internal memory and/or programming fault)

B1605

Fault symptom

Anti-theft alarm completely unserviceable. Indefinable (different functions may be affected, due to an internal memory and/or programming fault)

Conditions

Electronic control module fault (internal) generates diagnostic trouble code

Diagnostic procedure

1 Check the generation of the diagnostic trouble code

-	Clear the diagnostic trouble code

-	Drive the car on test

-	Check whether the diagnostic trouble code is generated afresh.

Is the DTC being registered?

yes

Continue with point 2.

no

The fault is intermittent.

2 Check the anti-theft alarm's electronic control module connection

-	Remove the electronic control module.

-	Check the connector for loose connector sleeves.

-	Check the control module's ground and power supply connections: -pin 25 (+30) -pin 10 (+15) -pin 13 (GND)

All OK?

yes

Refit the electronic control module and continue with point 3.

no

Take remedial action.

3 Check the generation of the diagnostic trouble code

-	Clear the diagnostic trouble code

-	Drive the car on test

-	Check whether the diagnostic trouble code is generated afresh.

Is the DTC being registered?

yes

See "Before replacing a control module".

no

The remedial measures taken were correct or the fault is of intermittent nature.