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Home >> Ford >> 2003 >> Thunderbird V8-3.9L VIN A >> Repair and Diagnosis >> Powertrain Management >> Computers and Control Systems >> Information Bus >> Testing and Inspection >> Pinpoint Tests >> Test B
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Test B

PINPOINT TEST B: THE FRONT ELECTRONIC MODULE (FEM) DOES NOT RESPOND TO THE DIAGNOSTIC TOOL


Test B1-B2:






Test B3-B4:






Test B4-B5:






Normal Operation
The FEM is a multifunction module. Power is supplied to the FEM through circuits 29-DK20 (OG/GN), 29S-DK22 (OG/YE) and 29S-DK21 (OG/WH). Circuit 31-DK20 (BK) provides the module ground. The FEM communicates with the diagnostic tool through the standard corporate protocol (SCP) communications network. Circuits 4-EG11 (GY) and 5-EG11 (BU) receive and transmit data from the FEM 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 29-DK20 (OG/GN) open or short to ground
- circuit 29S-DK21 (OG/WH) open or short to ground
- circuit 29S-DK22 (OG/YE) open or short to ground
- circuit 31-DK20 (BK) open
- circuit 4-EG11 (GY) open
- circuit 5-EG11 (BU) open
- FEM C201c
- FEM
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