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

C1 CHECK FOR AN OPEN BETWEEN THE DATA LINK CONNECTOR (DLC) C251 AND THE PCM C175
- 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 PCM C175-15, Circuit 915 (PK/LB), Harness Side And DLC C251-10, 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 PCM C175-16, Circuit 914 (TN/OG), Harness Side And DLC C251-2, 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 ELECTRONIC ENGINE CONTROLS . CLEAR the DTCs. REPEAT the self-test. CARRY OUT the data link diagnostics test.
- No : The system is operating correctly at this time. The 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.