Test Procedure
WARNING: This page is about a different car, the 2006 Mercury Mariner and 2006 Ford Escape. However, it is still accessible from the selected car via links, so may be relevant.
- AA1 CHECK FOR IGNITION RUN INPUT AT THE PCM
- Access the PCM and monitor the IGN_R PID.
- Key ON, engine OFF.
Does the PID indicate YES (key in ISP-R position)?
Yes No Key in OFF position. Key in OFF position. GO to AA2. GO to FE3 . - AA2 CHECK FOR IGNITION RUN/START INPUT AT THE PCM
- Access the PCM and monitor the IGN_R/S PID.
- Attempt to start the engine.
Does the PID indicate YES (key in ISP-R/S position during engine crank)?
Yes No Key in OFF position. Key in OFF position. GO to AA5. GO to AA3. - AA3 CHECK THE IGNITION RUN/START CIRCUIT FOR AN OPEN
- PCM connector disconnected.
- Turn the ignition key to the START position and hold.
- Measure the voltage between:
( + ) PCM Connector, Harness Side ( - ) Vehicle Battery ISP-R/S Negative terminal
Is the voltage greater than 10.5 V?
Yes No GO to AA4. CHECK for a damaged ignition switch.
REFER to COMPONENT TESTING .
If the ignition switch is OK, REPAIR the open circuit in the harness. - AA4 CHECK FOR GROUNDED IGNITION RUN/START CIRCUIT
- Key in OFF position.
- PCM connector disconnected.
- Measure the resistance between:
( + ) PCM Connector, Harness Side ( - ) Vehicle Battery ISP-R/S Negative terminal
Is the resistance greater than 10K ohms?
Yes No GO to AA9. CHECK the ignition switch for a short to ground. If OK, REPAIR the short to ground circuit in the harness. - AA5 CHECK THE VOLTAGE AND GROUND TO THE MODULES
- Key ON, engine OFF.
- Access the PCM and monitor the VBAT PID.
- Access the TCM and monitor the VBAT PID.
Are the voltages greater than 10.5 volts?
Yes No Key in OFF position. Key in OFF position. GO to AA6. REPAIR as necessary. - AA6 CHECK THE STATUS OF THE CONTACTORS
- Key ON, engine OFF.
- Access the TCM and monitor the CONTACT PID.
Is the PID state CLOSED?
Yes No Key in OFF position. Key in OFF position. GO to AA7. The traction battery voltage must be in the correct operating range for the contactors to close. REFER to HIGH VOLTAGE TRACTION BATTERY for traction battery diagnosis. - AA7 CHECK HIGH VOLTAGE BATTERY POWER AT THE TRANSAXLE ASSEMBLY
- Key ON, engine running.
- Access the TCM and monitor the M_INV_V and G_INV_V PIDs.
Are the voltages between 216 - 400 V?
Yes No Key in OFF position.
GO to AA8.Key in OFF position.
Diagnose the high voltage supply concern to the transaxle assembly.
GO to Pinpoint Test TT . - AA8 CHECK FOR THE CORRECT VEHICLE MODE
- Key ON, engine running.
- Access the TCM and monitor the VEHMODE PID.
Is the PID state DRIVING?
Yes No Key in OFF position.
The PCM and the transaxle assembly are not the cause of the engine no start.
REFER to SYMPTOM CHARTS .Key in OFF position.
GO to AA9. - AA9 CHECK FOR CORRECT PCM OPERATION
- Disconnect all the PCM connectors.
- Visually inspect for:
- pushed out pins
- corrosion
- Connect all the PCM connectors and make sure they seat correctly.
- Carry out the PCM self-test and verify the concern is still present.
Is the concern still present?
Yes No INSTALL a new PCM. REFER to FLASH ELECTRICALLY ERASABLE PROGRAMMABLE READ ONLY MEMORY (EEPROM) . The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector.