Pinpoint Test A: The Pcm Does Not Respond To The Scan Tool

WARNING: This page is about a different car, the 2009 Ford Econoline. However, it is still accessible from the selected car via links, so may be relevant.

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

NOTE: Failure to disconnect the battery when instructed will result in false resistance readings. Refer to BATTERY, MOUNTING AND CABLES .

A1 VERIFY WHETHER OTHER HS-CAN MODULES PASS THE NETWORK TEST
- Enter the following diagnostic mode on the scan tool: Network Test.
- In the LH pane of the IDS network test display screen, verify whether any HS-CAN modules passed the network test.
- Is the text "pass" or a DTC listed next to any of the following modules (if equipped): ABS module, Instrument Cluster (IC), Restraints Control Module (RCM), PCM, Trailer Brake Control (TBC) module?
- Yes: If "pass" or a DTC was listed next to the PCM, a network fault is not currently present. Go To PINPOINT TEST L to diagnose an intermittent HS-CAN fault condition.
  If "pass" or a DTC was listed next to one or more modules other than the PCM, GO to A2 .
- No: No modules are currently communicating on the HS-CAN . Go To PINPOINT TEST K to diagnose no HS-CAN communication.
A2 VERIFY THE PC/ED MANUAL PINPOINT TEST QA HAS BEEN CARRIED OUT
- Verify that Powertrain Control/Emissions Diagnosis (PC/ED) manual pinpoint test QA (gasoline engine) or AE (diesel engine) has been carried out.
- Has the PC/ED pinpoint test been carried out?
- Yes: GO to A3 .
- No: REFER to the INTRODUCTION - GASOLINE MODELS pinpoint tests to diagnose no communication with the PCM.
A3 CHECK THE HS-CAN TERMINATION RESISTANCE
- Ignition OFF.
- Disconnect: Negative Battery Cable.
- Measure the resistance between the Data Link Connector (DLC) C251-6, circuit VDB04 (WH/BU), harness side and the DLC C251-14, circuit VDB05 (WH), harness side.
  
  Fig 1: Measuring Resistance Between Data Link Connector (DLC) C251-6, Circuit VDB04 (WH/BU) And C251-14, Circuit VDB05 (WH)
  Courtesy of FORD MOTOR CO.
- Is the resistance between 54 and 66 ohms?
- Yes: CONNECT the negative battery cable. GO to A5.
- No: GO to A4 .

A4 CHECK THE HS-CAN CIRCUITS BETWEEN THE PCM AND THE DLC FOR AN OPEN

Disconnect: PCM C175b.

Measure circuit VDB04 (WH/BU) resistance between the PCM, harness side, and the DLC , harness side, as follows:

RESISTANCE REFERENCE

Engine	PCM Connector-Pin DLC	Connector-Pin
4.6L and 5.4L	C175b-59	C251-6
6.8L	C1551b-11	C251-6
6.0L Diesel	C1381b-13	C251-6

Measure circuit VDB05 (WH) resistance between the PCM, harness side, and the DLC , harness side, as follows:

RESISTANCE REFERENCE

Engine	PCM Connector-Pin	DLC Connector-Pin
4.6L and 5.4L	C175b-43	C251-14
6.8L	C1551b-23	C251-14
6.0L Diesel	C1381b-14	C251-14

Are the resistances less than 5 ohms?

Yes: CONNECT the negative battery cable. GO to A5 .
No: REPAIR the circuit in question. CONNECT the negative battery cable. CLEAR the DTCs. REPEAT the network test with the scan tool.

A5 CHECK FOR CORRECT PCM OPERATION
- Disconnect all the PCM connectors.
- Check for:
  - corrosion
  - damaged pins
  - pushed-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 - GASOLINE ENGINES or ELECTRONIC ENGINE CONTROLS - DIESEL ENGINE . CLEAR the DTCs. REPEAT the network test with the scan tool.
- 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 network test with the scan tool.