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Test I

PINPOINT TEST I: THE REAR ELECTRONIC MODULE (REM) DOES NOT RESPOND TO THE DIAGNOSTIC TOOL


Test I1-I2:






Test I3-I4:






Test I4-I5:






Normal Operation
The REM is a multifunction module. Power is supplied through circuits 29S-DK31 (OG/BK) and 30-DK31 (RD/GN). Circuit 31-DK30 (BK/OG) provides the module ground. The REM communicates with the diagnostic tool through the standard corporate protocol (SCP) communications network. Circuits 4-EG12 (GY/WH) and 5-EG12 (BU/OG) receive and transmit data from the REM to the data link connector (DLC) through the interior auxiliary junction box (AJB). Degraded SCP performance occurs if one bus line is open, shorted to ground or voltage, or if one but not all termination resistors are lost.

Possible Causes
- circuit 29S-DK31 (OG/BK) open or short to ground
- circuit 30-DK31 (RD/GN) open or short to ground
- circuit 31-DK30 (BK/OG) open
- circuit 4-EG12 (GY/WH) open
- circuit 5-EG12 (BU/OG) open
- REM 420c
- REM