Pinpoint Test H: U0100:87

Refer to MODULE COMMUNICATIONS NETWORK for schematic and connector information.

Normal Operation and Fault Conditions

In addition to communicating over HS-CAN, the GSM and SOBDMC communicate over a private Powertrain CAN. If the GSM does not receive expected messages from the SOBDMC, it will set a DTC.

DTC Fault Trigger Conditions

DTC	Description	Fault Trigger Condition
GSM U0100:87	Lost Communication With ECM/PCM "A": Missing Message	For this vehicle, this DTC indicates the GSM did not receive some or all of an expected message from the SOBDMC over the private Powertrain CAN.

Possible Sources

Low system voltage
Circuit open or shorted
Incorrect PMI
Connectors damaged or pushed-out terminals, corrosion, loose wires and missing or damaged seals
SOBDMC fault

H1 CHECK THE GSM (GEAR SHIFT MODULE) FOR DIAGNOSTIC TROUBLE CODES (DTCS)

NOTE: If a GSM self-test is carried out, the driver door must be fully closed. A false P166B DTC may set if the driver door is not fully closed during the self-test.
- Using a diagnostic scan tool, carry out the GSM self-test.
Are any system voltage or internal module diagnostic trouble codes (DTCs) present in the GSM?

Yes RESOLVE those diagnostic trouble codes (DTCs) first. REFER to the GSM DTC Chart, Diagnostic Trouble Code (DTC) Chart .

No GO to H2

H2 CHECK THE SOBDMC (SECONDARY ON-BOARD DIAGNOSTIC CONTROL MODULE C) FOR DIAGNOSTIC TROUBLE CODES (DTCS)

Using a diagnostic scan tool, carry out the SOBDMC self-test.

Are any diagnostic trouble codes (DTCs) present in the SOBDMC?

Yes	RESOLVE those diagnostic trouble codes (DTCs) first. REFER to the Master DTC Chart.

No	If the SOBDMC does not respond to the diagnostic scan tool, REFER to: Controller Area Network (CAN) Module Communications Network . Otherwise, GO to H3

H3 CHECK FOR OTHER CAUSES OF COMMUNICATION CONCERNS

NOTE: If new modules were installed prior to the DTC being set, the module configuration can be incorrectly set during the PMI or the PMI may not have been carried out.
- Check the vehicle service history for recent service actions related to the SOBDMC or to the GSM. If recent service history is found:
  - verify correct replacement module was installed
    - HVBOM may be used to verify correct part application
  - verify the configuration of replacement module was correct
    - re-configure module using as-built data if prior configuration is suspect
  - verify the module was not obtained from a like vehicle and installed into customer vehicle
    - return the swapped module to source vehicle and obtain new replacement module
Were any causes of a communication concern found in the vehicle service history?

Yes PROGRAM or INSTALL a new module as necessary.

No GO to H4

H4 ATTEMPT TO DUPLICATE THE DTC (DIAGNOSTIC TROUBLE CODE)

NOTE: If a GSM self-test is carried out, the driver door must be fully closed. A false P166B DTC may set if the driver door is not fully closed during the self-test.

Using a diagnostic scan tool, clear all diagnostic trouble codes (DTCs) from the GSM.

Road test the vehicle.

Using a diagnostic scan tool, carry out the GSM self-test.

Did DTC U0100:87 return?

Yes

GO to H5

No	The system is operating correctly at this time. The concern may have been caused by a high network traffic event or an intermittent fault condition.

H5 CHECK THE POWERTRAIN CAN (CONTROLLER AREA NETWORK) CIRCUITS FOR AN OPEN

Ignition OFF.

Disconnect GSM C3245.

Disconnect SOBDMC C3471D.

Inspect the connectors for damaged or pushed-out terminals.

Measure:

Positive Lead	Measurement / Action	Negative Lead
C3245-13	Courtesy of FORD MOTOR COMPANY	C3471D-32
C3245-14	Courtesy of FORD MOTOR COMPANY	C3471D-22

Are the resistances less than 3 ohms?

Yes

GO to H6

No	REPAIR the open circuit.

H6 CHECK THE POWERTRAIN CAN (CONTROLLER AREA NETWORK) CIRCUITS FOR A SHORT TO GROUND

Measure:

Positive Lead	Measurement / Action	Negative Lead
C3245-13	Courtesy of FORD MOTOR COMPANY	Ground
C3245-14	Courtesy of FORD MOTOR COMPANY	Ground

Are the resistances greater than 10, 000 ohms?

Yes

GO to H7

No	REPAIR the short to ground.

H7 CHECK FOR CORRECT SOBDMC (SECONDARY ON-BOARD DIAGNOSTIC CONTROL MODULE C) OPERATION

NOTE: If a GSM self-test is carried out, the driver door must be fully closed. A false P166B DTC may set if the driver door is not fully closed during the self-test.

Ignition OFF.

Disconnect and inspect all SOBDMC connectors.

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

Connect all SOBDMC connectors. Make sure they seat and latch correctly.

Connect all other electrical connectors that were previously disconnected.

Using the diagnostic scan tool, clear all diagnostic trouble codes (DTCs).

Road test the vehicle.

Carry out the GSM self-test.

Did DTC U0100:87 return?

Yes	CHECK for an applicable TSB, GSB, SSM, or FSA. If a service bulletin exists for this concern, discontinue this test and follow bulletin instructions. If none address this concern, INSTALL a new SOBDMC. REFER to: Inverter System Controller [SOBDMC] .

No	The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. ADDRESS the root cause of any connector or pin issues.