Pinpoint Test L: DTCs U1027, U1040, U1051, U1058, AND U1134

WARNING: This page is about a different car, the 2005 Lincoln LS. However, it is still accessible from the selected car via links, so may be relevant.

L1 RETRIEVE THE RECORDED DTCS FROM BOTH THE CONTINUOUS AND ON-DEMAND SELF-TESTS - SPEED CONTROL ACTUATOR
- Check for recorded speed control actuator DTCs from the continuous and on-demand self-test.
- Are any DTCs recorded
- Yes : For DTC U1027, GO to L2.
  For DTC U1040, GO to L3.
  
  For DTC U1051, GO to L4.
  
  For DTC U1058, GO to L5.
  
  For DTC U1134, GO to L6.
- No : GO to the SYMPTOM CHART in this article .
L2 MONITOR THE ENGINE RPM
- Key in ON position.
- Enter the following diagnostic mode on the diagnostic tool: PCM PID.
- Monitor the powertrain control module (PCM) engine RPM PID.
- Do the PID values agree with the engine RPM
- Yes : GO to L7.
- No : See INTRODUCTION - GASOLINE article to continue diagnosis of the engine speed.
L3 MONITOR THE VEHICLE SPEED SENSOR (VSS) SIGNAL
- Key in ON position.
- Enter the following diagnostic mode on the diagnostic tool: ABS PID.
- Monitor the anti-lock brake system (ABS) module VSS signal PID.
- Do the PID values agree with the speed signal?
- Yes : GO to L7.
- No : REFER to ANTI-LOCK CONTROL to continue diagnosis of the VSS signal.
L4 MONITOR THE ABS MODULE STOPLAMP SWITCH
- Key in ON position.
- Enter the following diagnostic mode on the diagnostic tool: ABS Module PID.
- Check the speed control actuator for correct operation by monitoring the ABS stoplamp switch signal PID.
- Do the PID values agree with the stoplamp switch signal?
- Yes : GO to L7.
- No : REFER to ANTI-LOCK CONTROL to continue diagnosis of the stoplamps.
L5 MONITOR THE PRNDL
- Key in ON position.
- Enter the following diagnostic mode on the diagnostic tool: PCM PID.
- Monitor the PCM digital transmission range (TR) sensor PID while selecting different gear positions.
- Do the PID values agree with the PRNDL display?
- Yes : GO to L7.
- No : REFER to AUTOMATIC TRANSAXLE/TRANSMISSION - 5R55S to continue diagnosis of the digital TR sensor.
L6 MONITOR THE IGNITION SWITCH PID
- Key in ON position.
- Enter the following diagnostic mode on the diagnostic tool: Instrument Cluster PID.
- Monitor the instrument cluster ignition switch PID while selecting different switch positions.
- Do the PID values agree with the switch position?
- Yes : GO to L7.
- No : REFER to STEERING COLUMN SWITCHES to continue diagnosis of the ignition switch.
L7 CHECK FOR CORRECT EPB MODULE OPERATION
- Disconnect the EPB module connectors.
- Check for:
- corrosion
- pushed-out pins
- Connect the EPB module connectors and make sure it seats correctly.
- Operate the system and verify the concern is still present.
- Is the concern still present?
- Yes : INSTALL a new EPB module. REFER to PARKING BRAKE MODULE in this article . CLEAR the DTCs. REPEAT the self-test. RESET the EPB system. REFER to ELECTRONIC PARKING BRAKE (EPB) RESETTING in this article .
- 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. RESET the EPB system. REFER to ELECTRONIC PARKING BRAKE (EPB) RESETTING in this article .