A/C - Erroneous Compressor Fault Code # 85

90bmw20 Group 64 Heating and Air Conditioning
Bulletin Number 64 07 90 (3151)
Woodcliff Lake, NJ November 1990 Service Engineering
SUBJECT: IHKR-II Sporadic Defects

MODELS: 525i - E34 (all so equipped)

Situation: With the introduction of the M50 engine and DME M3.1 engine management system, fault code 85 "A/C Compressor" may be encountered when reading the DME fault memory. This erroneous fault entry is due to overlapping IHKR II self-test and DME fault check.

Correction: Revised software is under development to prevent this situation.

If this fault code is encountered, and no air conditioning complaints exist, clear the fault memory and perform no diagnostic work for this fault code.

Important
Note: If no air conditioning complaints are present in conjunction with this fault code, no parts should be replaced and no troubleshooting should be performed, as there is no adverse effect on the performance of either the DME or IHKR II Systems.