Pinpoint Test

CHECK THE PCM FOR DTCs
1. Ignition ON.
2. Using a scan tool, perform a PCM self-test.
  Is DTC P0645:00 present?
  - Yes: REFER to Diagnostic Routine B: P0645:00 .
  - No : GO to 2 .
CHECK THE A/C COMPRESSOR CLUTCH ENGAGEMENT WITH RELAY DISCONNECTED
1. Ignition OFF.
2. Disconnect: A/C Clutch Relay.
3. KOER.
4. With the engine running, observe the A/C compressor clutch.
  Is the A/C compressor on?
  - Yes: GO to 3 .
  - No : GO to 5.

CHECK THE POWER CIRCUIT TO THE A/C CLUTCH FOR A SHORT TO POWER

Ignition OFF.
Disconnect: A/C Clutch Relay.
Ignition ON.

Measure:

BJB			Ground

A/C Clutch Relay Socket			Ground
Pin	Circuit	Measurement / Action	Pin	Circuit
5	CH401 (VT/WH)		-	-

Is any voltage present?

Yes: REPAIR the circuit.
No : GO to 4 .

CHECK THE A/C COMPRESSOR CLUTCH AIR GAP
1. Measure the A/C compressor clutch air gap at 3 equally spaced locations between the clutch hub and the A/C compressor clutch pulley.
  
  Fig 1: Measuring A/C Compressor Clutch Air Gap With Specification
  Courtesy of FORD MOTOR CO.
  
  Is the A/C compressor clutch air gap less than 0.35 mm (0.0138 in)?
  - Yes: ADJUST the A/C compressor clutch gap. REFER to Air Conditioning (AC) Clutch Air Gap Adjustment .
  - No : INSTALL a new A/C compressor clutch field coil.
CHECK THE A/C CLUTCH RELAY FUNCTIONALITY
1. Using a known good A/C clutch relay, check the A/C compressor clutch for correct operation.
  Is the A/C compressor on?
  - Yes: INSTALL a new A/C clutch relay.
  - No : GO to 6 .
CHECK FOR CORRECT PCM OPERATION
1. Ignition OFF.
2. Disconnect and inspect all PCM connectors.
3. Repair:
  - corrosion (install new connector or terminals - clean module pins)
  - damaged or bent pins - install new terminals/pins
  - pushed-out pins - install new pins as necessary
4. Reconnect the PCM connectors. Make sure they seat and latch correctly.
5. Operate the system and determine if the concern is still present.
  Is the concern still present?
  - Yes: CHECK OASIS for any applicable TSBs . If a TSB exists for this concern, DISCONTINUE this test and FOLLOW TSB instructions. If no TSBs address this concern, INSTALL a new PCM:
    REFER to POWERTRAIN CONTROL MODULE (PCM) - 2.0L GTDI , or
    
    REFER to POWERTRAIN CONTROL MODULE (PCM) - 3.5L TI-VCT .
  - No : The system is operating correctly at this time. The concern may have been caused by module connections. ADDRESS the root cause of any connector or pin issues.