FREE REPAIR MANUALS & LABOR GUIDES 1982-2013 Vehicles
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Central Locking System

FAULT DIAGNOSIS HINTS
1. Check that fuses 25 and 20 are intact and supplied with current.
2. Check that current is present on pins 4 and 3 of the control module.
3. Check that current is present on pin 7 of the control module when the doors are being locked and on pin 8 when they are being unlocked.

IMPORTANT:
Since pins 7 and 8 of the control module are supplied with current for only about 1 second, instrument readings must be taken at the exact moment the locking mechanism switches over.

Note also that the actuating motors (on testing) should be connected only to pins 7 and 8 of the control module. Otherwise the motors could be overloaded and damaged.

When the control module is not activated, pins 7 and 8 are both connected to ground.

4. Check the connectors, wiring harness and ground connections.