Instruments - Voltage Surges, Check Engine Light Circuit
Group 12Engine - Electric
Bulletin Number
12 08 88 (1687)
Woodcliff Lake, NJ
September 1989
Technical Dept.
This Service Information bulletin supersedes S.I. 12 08 88 (1687) dated January 1989. It lists the chassis numbers of the affected vehicles.
Please remove and discard, S.I. 12 08 88 (1687) dated January 1989 from your S.I. binder.
SUBJECT:
Motronic M1.1 - Circuit Suppression
MODELS:
528e (1988 model only)
Situation:
Migrant voltage surges from the "CHECK ENGINE" light circuit can affect M1.1 control unit durability. The procedure which follows will protect the M1.1 control unit and thus insure reliable performance.
Vehicles Affected:
Model Chassis No. Range
528e 983 0398 - 983 4271
528eA 971 3140 - 971 4999
988 5000 - 989 1999
990 0000 - 990 2486
Correction:
Install suppression diode harness (P/N 88 88 2 000 101).
Implementation:
This important preventative repair is vital in our combined effort to insure BMW customer satisfaction. Your support and cooperation in this Service Action is highly appreciated.
Please review your records and contact those customers whose vehicles are In the above mentioned chassis number range and which have not had this Service Action performed. Further, all vehicles in dealer inventory should receive this quick update prior to retail sale (i.e. P.D.I., used vehicle reconditioning, etc.).
Procedure:
1. Locate engine connector C-101 at fuse box. See Illustration "A".
2. Unclip O2 sensor heater relay with plug still attached and lay aside.
3. Remove fuse box lid and, slide up and remove C-101 black weather hood.
4. Pinch C-101 retaining hooks inward toward plug body and unplug C-101 (with Ignition switched OFF). See Illustration "B".
5. Locate female receptacle # 5 via small number beside pin (wire color-gray).
6. Release and withdraw receptacle from connector using BMW special tool P/N 81 24 9 408 087 (BMW Electrical Kit 1).
7. Insert female end of new diode harness in vacant position # 5 of C-101 multiplug. See Illustration "C".
8. Route diode harness around C-101 multi-plug so that diode is vertical and without bends. Harness should pass under upper retaining hook as indicated.
9. Plug diode harness male pin into former # 5 female connector.
10. Wrap former # 5 connector locking splines with electrical tape. Partially insert connected assembly into harness wiring.
11. Reconnect C-101 multi-plug to fuse box, being certain to latch upper and lower retaining hooks.
12. Reinstall black weather hood over C-101 multiplug/fuse box connection.
13. Reinstall O2 sensor heater relay and plug to side of fuse box.
14. Reinstall fuse box lid.
15. Check "CHECK ENGINE" light operation.
Service Action Label Instructions:
This Service Action has been assigned code number 15. After the prescribed work has been performed, obtain a label (P/N 01 99 9 750 968) and
a) emboss your BMW dealer warranty number in the middle of the label;
b) punch out code number 15 printed on the label;
c) bend label to crease an edge and remove the backing paper. Then affix it to the "B" pillar (on driver's front door) as shown.
Parts Information:
When ordering new diode harness (P/N 88 88 2 000 101) one order = one diode harness.
Warranty Status:
Reimburseable under the terms of the BMW Emissions warranty of 5 Years/50,000 Miles.
Main Work Associated Work
Defect Code: 00 00 12 53 00 00 00 12 53 00
Labor operation: 00 50 155 00 50 755
Labor allowance: 3 FRU 2 FRU
NOTE:
The following explanations will explain the correct use of the work times.
Main Work:
Use this time when the only repair performed is the listed warranty repair.
OR
Associated Work:
Use this time when other repairs or services are performed along with the listed warranty repair.
Under no circumstances should both work times be claimed. Attempts to claim both times will result in an unnecessary delay in claim processing and payment.