Locks - Activated When Ignition is Turned OFF

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Bulletin
89-10-16A

Date
June, '89

Ref. No.
89-078A-10

Corp. Ref. No.
901601R


SUBJECT:
AUTOMATIC DOOR LOCKS (OPTION AU4) ACTIVATED TO LOCK POSITION WHEN IGNITION IS TURNED OFF

MODELS AFFECTED:
1985-89 ELECTRA/PARK AVENUES

This bulletin has been revised to clarify Parts Kit usage and to let dealers know the Zener Diode is included in Kit No. 25535774. Bulletin replaces 89-10-16 (901601R).


The above condition can occur on any 1985 thru 1989 Electra and Park Avenue vehicles. It is most likely to occur on vehicles with Nippondenso fuel pumps.

The fuel pump armature spins after the ignition is turned off. The armature then acts as a generator that can transmit a transient electrical pulse into the automatic door lock (ADL) circuit causing the doors to lock.

DEALER ACTION

To prevent the electrical pulse from entering the ADL circuit, a zener diode can be added. The diode blocks the pulse.

NOTICE:
Be certain to install the zener diode in the proper direction. Follow the instructions carefully. Improper installation will not correct the condition. Obtain Diode Kit, Part Number 25535774 from GMSPO.

1. Disconnect battery negative cable.

2. Open glove box (1) fully pull rubber retainers (2).





3. Disconnect ADL controller (3) from connector bracket (see Figure 1).





4. Cut and strip pink/black wire (connector terminal "C") (see Figure 2).

5. Slip heat shrink tubing over wire.

6. Use wire splice clips to install diode. Install diode as shown in Figure 2 with silver band end towards fuse 16. Use care to ensure the diode is installed properly.

7. Fold wires and diode as shown in Figure 2.





8. Slide heat shrink tubing over diode and shrink. Figure 3 shows the revised schematic.

9. Connect ADL controller to connector bracket.

10. Reinstall glove box door part retainers.

11. Reconnect battery negative cable.

12. Reprogram all electronic systems, set clock, etc.

Parts are currently available from GMSPO.

WARRANTY INFORMATION

Labor Operation Number:
T5187
Labor Time:
0.2 Hour
Trouble Code:
92