Pinpoint Test C: The Powertrain Control Module (Pcm) Does Not Respond To The Diagnostic Tool

C1 CHECK FOR AN OPEN BETWEEN THE DLC C251 AND THE PCM C175a
- Key in OFF position.
- Disconnect: PCM C175.
- Measure the resistance between the PCM C175-15, circuit 915 (PK/LB), harness side and the DLC C251-10, circuit 915 (PK/LB), harness side.
  
  Fig 1: Measuring Resistance Between The PCM C175-15, Circuit 915 (PK/LB), Harness Side And The DLC C251-10, Circuit 915 (PK/LB), Harness Side
  Courtesy of FORD MOTOR CO.
- Measure the resistance between the PCM C175-16, circuit 914 (TN/OG), harness side and the DLC C251-2, circuit 914 (TN/OG), harness side.
  
  Fig 2: Measuring Resistance Between The PCM C175-15, Circuit 915 (PK/LB), Harness Side And The DLC C251-10, Circuit 915 (PK/LB), Harness Side
  Courtesy of FORD MOTOR CO.
- Are the resistances less than 5 ohms?
Yes

GO to C2

No

REPAIR the circuit in question. CLEAR the DTCs. REPEAT the self-test. CARRY OUT the data link diagnostics test.
C2 CHECK FOR CORRECT PCM OPERATION
- Disconnect all the PCM connectors.
- Check for:
  - Corrosion
  - push-out pins
- Connect all the PCM connectors and make sure they seat correctly.
- Operate the system and verify the concern is still present.
- Is the concern still present?
Yes

INSTALL a new PCM. Refer to INTAKE AIR, FUEL CHARGING, & ENGINE ELECTRONICS CLEAR the DTCs REPEAT the self-test. CARRY OUT the data link diagnostics test.

No

The system is operating correctly at this time. Concern may have been caused by a loose or corroded connector. CLEAR the DTCs. REPEAT the self-test. CARRY OUT the data link diagnostics test.