SI07.15-W-0017A | Service Information: Exchange of engine control (MR) control unit | 12.5.04 |
ENGINE 541.9 in MODEL 930, 932, 933, 934, 950, 952, 953, 954
ENGINE 542.9 in MODEL 930, 932, 934, 950, 952, 954
After installing a new engine control (MR) control unit with software release 56, the oil pressure indicator lamp may sometimes light up if an oil pressure sensor is installed on the engine instead of an oil pressure switch. The fault code 02020 is simultaneously stored in the engine control (MR) control unit.
The reason is that in all engine control (MR) control units supplied as replacement parts, parameter 26 was permanently set to oil pressure switch and this parameter could afterwards not be changed.
This means that when the engine control (MR) control unit was replaced, the oil pressure sensor had to be replaced with an oil pressure switch.
Starting with the following STAR DIAGNOSIS CD release, parameter 26 in the engine control (MR) control unit can be changed:
Model 950, 952, 953, 954: as of STAR DIAGNOSIS CD 10/2003
Model 930, 932, 933, 934: as of STAR DIAGNOSIS CD 11/2003
It is therefore no longer necessary to replace the oil pressure sensor with an oil pressure switch when exchanging engine control (MR) control units in these two model series.