Instruments - Voltage Surges, Check Engine Light Circuit
90bmw05GROUP 12 Engine - Electric
Bulletin Number 12 07 88 (1678) Page 1 of 4
Woodcliff Lake, NJ January 1990 Service Engineering
This Service Information bulletin supersedes SI 12 07 88 (1678) dated September 1989. It lists revised chassis numbers of the affected vehicles.
Please remove and discard SI 12 07 88 (1678) dated September 1989 from your S.I. binder.
SUBJECT: Motronic M1.1 - Circuit Suppression
MODELS: E32 (735i), E30, E24, Equipped with M1.1 Fuel Injection - 1987 and 1988 Model Years (prior to 5.88 production)
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:
Correction: Install suppression diode harness (P/N 88 88 2 000 100).
Implementa-
tion: 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 the main engine connector (X.20 on E32 or C-101 on E24, E30)
2 - Unscrew engine connector and separate connector halves (with ignition switched OFF)
3 - Pull back rubber boot on connector plug section (containing male pins) using a dull-edged tool - do not perforate or tear rubber boot.
Illustration "A":
4 - Release electrical pin latching collar by disengaging locking tabs and rotate collar counterclockwise. See illustration "A".
5 - Locate male electrical pin # 12 via a small number beside pin (wire color:
early production - brown; later production - gray).
6 - Release and withdraw pin from engine connector using BMW special tool
P/N 88 88 6 611 110 (refer to S.I. 04 06 87 (1357). See illustration "A".
Illustration "B":
7 - Insert male end of new diode harness in vacant pin # 12 opening. Make certain that the pin locks in place. See illustration "B".
Illustration "C":
8 - Route diode harness in a circular fashion inside engine connector. See illustration "C".
9 - Plug in former # 12 pin in the female end of the diode harness.
10 - Wrap electrical tape over former # 12 pin body to protect other wires from
pin (locking) splines.
11 - Slide the finished assembly partially into sheath covering. See illustration
"C".
12 - Rotate latching collar clockwise to relatch all pins.
13 - Snap engine connector rubber boot back in place.
14 - Join engine connector upper and lower halves together.
Illustration "D":
15 - Lock connector halves together as follows:
^ align any of the key lines with the arrow on upper connector half. See illustration "D".
^ rotate lock ring 1200 (1/2 of a turn) until a "click" is heard/felt. Ring is seated and locked when adjacent key line is aligned with arrow.
16 - Check "CHECK ENGINE" light operation.
Service Action Label
Instructions: This Service Action has been assigned code number 12. 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 12 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 diode harness (P/N 88 88 2 000 100) one order = one diode harness.
Warranty
Status: Reimburseable under t'he terms of the BMW Emissions Warranty of 5 Years/50,000 Miles.
Main Associated
Work 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.