DME/Diagnostic Module Testing (13 05 90 (3056))

Publication date: 1990-04-01
Reference number: 13 05 90 (3056)

DME/DIAGNOSTIC MODULE TESTING

TECHNICAL SERVICE BULLETIN

Reference Number(s): 13 05 90 (3056)

DME/DIAGNOSTIC MODULE TESTING

Model(s): 1990 BMW 525i, 535i (produced 1/90 thru 5/90)

Group: 13 - Fuel System

Bulletin No.: 13 05 90 (3056)

Date: April, 1990

SITUATION

The listed vehicles may encounter the following problems when using the BMW diagnostic module:

FAULT 1

When attempting to establish the diagnostic link, the VDU reads "DME control unit not found".

FAULT 2

DME fault code #40 A/C compressor sets (erroneously) in DME fault memory.

CAUSE

The new IHKR II system causes interference with the DME system during initial system self-testing.

SOLUTION

FAULT 1

Remove fuse F9 from the front power distribution box before turning the ignition switch ON. When the diagnostic link is established, reinstall fuse F9.

FAULT 2

Disregard DME fault code #40 if no air conditioning complaint exists.

IDENTIFICATION

The new IHKR II system can be visually identified noting the changes in the IHKR control panel. See Fig 1 .

Fig 1: IHKR II System Identification

IMPORTANT: At present the above situations cannot be corrected by replacement of the DME or the IHKR II control units.