P1602

P1602
Power Supply (B+ permanent) - too Low
Power Supply - Interruption

Function
The memory components are supplied with voltage by terminal 30. If terminal 30 is interrupted (for instance if the battery is disconnected), the adaptation values are erased.

Diagnostic conditions
Continuous RAM monitoring of control bytes faulty.

NOTE: This DTC does not necessarily mean that a fault exists. This DTC is also recorded in memory when the battery or the ECM is disconnected. In such cases erase the DTC memory and road test the vehicle.





Wiring Diagram.





Diagnostic procedure
Check wiring for terminal 30 for continuity.
1. Remove connector X 4/2.
2. Connect voltmeter on cavity side to pin 1 (plus) and ground.

- Specified value: battery voltage
- If meter does not read battery voltage, check wiring from connector X 4/2, pin 1 to central electric fuse/relay panel connector D 15 for continuity.
- Check connectors for corrosion.

3. Reconnect connection X 4/2.
4. Remove ECM connector.
5. Connect voltmeter to pin 26 (plus) and ground.

- Specified value: battery voltage
- If meter does not read battery voltage, check wiring from ECM connector, pin 26 to connector X 4/2, pin side to pin 1 for continuity. - Check connectors for corrosion.