P0652-SENSOR REFERENCE VOLTAGE 2 CIRCUIT LOW





For a complete wiring diagram Refer to Section 8W.


  • When Monitored:

    Ignition on.

  • Set Condition:

    When the PCM recognizes the Auxiliary 5-volt Supply circuit voltage is too low. One Trip Fault. ETC light is flashing.


Possible Causes
 
(F856) AUXILIARY 5-VOLT SUPPLY SHORTED TO GROUND
 
SENSOR SHORTED TO GROUND
 
CAM POSITION SENSOR
 
PCM
 


Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING).



Diagnostic Test

1.ACTIVE DTC



NOTE: Improperly installed aftermarket accessories can cause this DTC to set. Check for wiring added by customer.



Is the DTC Active at this time?

Yes
  • Go To 2


No

2.(F856) AUXILIARY 5-VOLT SUPPLY SHORTED TO GROUND








Is the resistance below 100 ohms?

Yes


No
  • Go To 3

3.CMP SENSOR








Is the voltage below 4.5 volts?

Yes
  • Go To 4


No

4.5-VOLT SENSOR SHORTED TO GROUND




NOTE: You must Turn the Ignition OFF when disconnecting any of the Sensor harness connectors and Turn the Ignition On to check the voltage readings.




Does the voltage increase above 4.5 volts when disconnecting any of the Sensor harness connectors?

Yes


No
  • Go To 5

5.PCM

NOTE: Before continuing, check the PCM harness connector terminals for corrosion, damage, or terminal push out. Repair as necessary.




Were there any problems found?

Yes


No