Service Action-Engine Control Module Self Activation (12 02 93 (3922))

SERVICE ACTION-ENGINE CONTROL MODULE SELF ACTIVATION

TECHNICAL SERVICE BULLETIN

SERVICE ACTION - ENGINE CONTROL MODULE RELAY SELF-ACTIVATION

Model(s): 1994 BMW 540i w/M60 engine & adaptive transmission control

Group: 12 - Engine Electrical

Bulletin No.: 12 02 93 (3922)

Date: February, 1994

SITUATION

Due to component changes with the introduction of AGS, the engine control module main relay may self-activate due to a current back feed after the ignition has been turned off and the engine has stopped. This does not cause the engine to start. The battery may become discharged due to the current required to power the control modules.

VEHICLES AFFECTED

Vehicles produced from 8-16-93 through 10-13-93 may be affected. In order to determine if a specific vehicle is to be inspected under this Service Action, it will be necessary to utilize the "Service Menu" of the DCS (Dealer Communication System). Proceed to "Inquiries;" "Vehicle History" and enter the chassis number (last seven characters) of the vehicle in question. Based on the response of the system, either proceed with the required corrective actions or take no further action.

The Chassis Number Ranges listed below are only for informationalpurposes and are not to be considered as the only deciding factor. The affected vehicles are limited to vehicles within these ranges, but not all of these vehicles are affected by the Service Action. The final decision factor is the DCS inquiry.

Model	Chassis Number Ranges
530iA	GE 86990 - GE 88208
530iA Touring	GF 80930 - GF 80978
540iA	GF 27370 - GF 28621, GF 27167

CORRECTION

The next time one of the affected vehicles is in the shop for maintenance or repair, such vehicle should be checked to determine if it is possible for the engine control module main relay to self-activate. If self-activation is possible, the engine control module is to be replaced.

REPAIR PROCEDURE

1. Inspect the engine control module white production sticker for the code "4459" (handwritten or printed) next to or under the 2nd bar code. See Fig 1 .
   Fig 1: Engine Control Module White Production Sticker

   

   If the control module white production sticker is marked with the code "4459", skip to the SERVICE ACTION LABEL INSTRUCTIONS  section.

2. With the ignition switched off, connect the 88-pin test adapter (special tool number 88 88 6 614 410) between the engine control module and its harness connector.
3. Connect the test Capacitor (Special tool number 90 88 6 129 490) between pins 28 and 54 of the 88-pin test adapter. See Fig 2 . Pay attention to the pin numbers on each end of the tool to ensure that it is installed correctly in the 88-pin test adapter.
   Fig 2: Test Capacitor Connection To 88-Pin Test Adapter

   
   NOTE: This test capacitor can only be used for this Service Action.
4. Switch on the ignition and start the engine. After the engine has run for one minute, switch off the ignition.
5. Immediately after switching off the ignition, listen to the engine control module relay to hear if it switches on and can be heard operating. See Fig 3 .
   Fig 3: K6300 - Engine Control Module Relay Location

   
   NOTE: Due to the high clocking frequency (approximately 50 to 100 Hz) of the relay if activated under this situation, the noise heard will be similar to a blower fan grazing its housing if the relay self activates.
6. If no clicking noise can be heard after the ignition has been switched off for one minute, there is no current back feed and the vehicle does not need repair.
7. If a continuous clicking noise can be heard from the engine control module main relay, the engine control module should be replaced with a modified version (code number "4459").

Model	Part Number	Part Name
530iA/iTA	12 14 1 748 865	Engine Control Module
540iA	12 14 1 740 028	Engine Control Module
SD 92-031		Service Action/Recall Campaign Label

SERVICE ACTION LABEL INSTRUCTIONS

The procedures outlined in this bulletin cover Service Action 106. After the vehicle has been checked, and corrected if necessary, obtain a label (SD 92-031) and:

A.) Emboss your BMW dealer warranty number in the middle of the label (1);

B.) Punch out code number 106 printed on the label (2): and

C.) Bend label to crease an edge and remove the backing paper. Then affix it to the "B" pillar as shown in Fig 4 .

If the vehicle already has a label from a previous Service Action/Recall Campaign, affix this label next to the old one. Do not affix one label on top of another one because a number from an underlying label could appear in the punched out hole of the new label.