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Home >> Lincoln >> 2003 >> LS V8-3.9L VIN A >> Repair and Diagnosis >> Powertrain Management >> Computers and Control Systems >> Information Bus >> Testing and Inspection >> Pinpoint Tests >> Communications Network >> Pinpoint Tests >> Test I
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Test I

PINPOINT TEST I: THE DRIVER SEAT MODULE (DSM) DOES NOT RESPOND TO THE DIAGNOSTIC TOOL


Test I1-I2:






Test I2-I3:






Test I4-I5:






Test I5-I6:






Test I7:






Normal Operation
The DSM communicates with the diagnostic tool through the SCP communications network circuits 4-AH80 (GY/WH) and 5-AH80 (BU/OG). If circuit 4-AH80 (GY/WH) or 5-AH80 (BU/OG) becomes open or shorted to ground, communications to that module will not be possible. Check circuits 4-AH80 (GY/WH) and 5-AH80 (BU/OG) between the DSM C341c and the DLC C251. Total resistance values must not be more than 5 ohms. If the resistance is more than 5 ohms, there is either an open in circuit 4-AH80 (GY/WH) or 5-AH80 (BU/OG), damage to the DLC C251, damage to the DSM C341c, or a problem with in-line interior auxiliary junction box (AJB) C283c, C283d or joint connector No.4 C223.

Possible Causes
- circuit 4-AH80 (GY/WH) or 5-AH80 (BU/OG) shorted to ground or open C341c
- interior AJB C283c, C283d
- joint connector No.4 C223
- DLC C251
- DSM
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