Engine Controls - Unable to Diagnose Using DIS Tester

GROUP 61
General Electrical Systems

Bulletin Number
61 03 97

Woodcliff Lake, NJ
May 1997
Product Engineering

SUBJECT:
Inability to Diagnose with DIS Tester or MoDiC

MODEL:
All

General Information:
Certain cases may be encountered in which diagnosis of one or more control modules is not possible with either the DIS Tester or MoDiC (Tester displays message: Selected Control Unit Not Found"). If battery voltage is below 12.4 volts, charge the battery. If the voltage is 12.4 volts or higher, before extensive troubleshooting is performed, proceed as follows:

* Disconnect positive and negative battery cables from the battery (from both batteries in the case of 8 Series vehicles).

* Using a fused jumper (such as BMW Special Tools, Part Numbers 88 88 6 611 458 or 88 88 6 611 476), briefly connect the ends of the positive and negative battery cables. This will dissipate any residual charges in the control modules which could hold them in a state of malfunction.

Note:
The cause of this problem could be a low battery or recent jump start.

* Reconnect the battery cables, and resume diagnosis.

Warranty Status:
Information Only.