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Pinpoint Test A: No Communication With The Generic Electronic Module

CAUTION: Use the correct probe adapter(s) when making measurements. Failure to use the correct probe adapter(s) may damage the connector.

A1 CHECK THE GENERIC ELECTRONIC MODULE (GEM) POWER SUPPLY

Key in OFF position.
Disconnect: Generic Electronic Module (GEM) C201a.
Disconnect: GEM C201b.
Key in ON position.

Using the following table, measure the voltage between the GEM, harness side and ground.

CONNECTOR & PIN REFERENCE CHART

Connector	Pin	Circuit
C201a	4	400 (LB/BK)
C201a	1	1006 (DG/WH)
C201b	2	1001 (WH/YE)
C201b	3	193 (YE/LG)

Are the voltages greater than 10 volts?

Yes : GO to A2.
No : REPAIR the circuit(s) in question. TEST the system for normal operation.

A2 CHECK THE GEM GROUND CIRCUIT 397 (BK/WH) FOR OPEN
- Key in OFF position.
- Measure the resistance between the GEM C201b pin 4, circuit 397 (BK/WH), harness side and ground.
  
  Fig 1: Measuring Resistance Between GEM C201B Pin 4, Circuit 397 (BK/WH), Harness Side And Ground
  Courtesy of FORD MOTOR CO.
- Is the resistance less than 5 ohms?
- Yes : GO to A3.
- No : REPAIR the circuit(s) in question. TEST the system for normal operation.
A3 CHECK CIRCUIT 397 (BK/WH) FOR SHORT TO POWER
- Measure the voltage between the GEM C201b pin 4, circuit 397 (BK/WH), harness side and ground.
  
  Fig 2: Measuring Voltage Between GEM C201B Pin 4, Circuit 397 (BK/WH), Harness Side And Ground
  Courtesy of FORD MOTOR CO.
- Is any voltage present?
- Yes : REPAIR the circuit. TEST the system for normal operation.
- No : refer to MODULE COMMUNICATIONS NETWORK .