P2100-ELECTRONIC THROTTLE CONTROL MOTOR CIRCUIT





For a complete wiring diagram Refer to Section 8W.


  • When Monitored:

    With the ignition on and the ETC Motor is not in Limp Home mode.

  • Set Condition:

    When the PCM detects an internal error or a short between the ETC Motor- and ETC Motor + circuits in the ETC Motor Driver. One trip fault. ETC light is flashing.


Possible Causes
  
THROTTLE PLATE / BORE INSPECTION
  
(K124) ETC POSITIVE CIRCUIT SHORTED TO BATTERY VOLTAGE
  
(K126) ETC NEGATIVE CIRCUIT SHORTED TO BATTERY VOLTAGE
  
(K124) ETC POSITIVE CIRCUIT SHORTED TO THE (K126) ETC NEGATIVE CIRCUIT
  
(K124) ETC POSITIVE CIRCUIT OPEN
  
(K124) ETC POSITIVE CIRCUIT SHORTED TO GROUND
  
(K126) ETC NEGATIVE CIRCUIT OPEN
  
(K126) ETC NEGATIVE CIRCUIT SHORTED TO GROUND
  
LOW BATTERY VOLTAGE
  
ETC MOTOR/THROTTLE BODY
  
PCM
  

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



Diagnostic Test

1.ACTIVE DTC


NOTE: When this DTC is Active the engine speed, torque, and vehicle speed are limited to a Limp in mode.


NOTE: If the P2100 is intermittent, it is possible that the controller is overheating in extreme hot temperatures, and this is considered a normal protection operation. No repair is necessary.


NOTE: Low battery voltage can also cause excessive current draw, in very hot and very cold ambient temperatures. Make sure the battery can pass a load test before continuing.





Is the DTC Active at this time?

Yes
  • Go To 2


No

2.THROTTLE PLATE INSPECTION





Were any signs of foreign material or scoring of the throttle plate or bore found?

Yes
  • Remove the debris if possible or replace the Throttle Body Assembly. Disconnect the Battery when replacing the Throttle Body Assembly. After installation is complete, use a scan tool and select the ETC RELEARN function.
  • Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)


No
  • Go To 3

3.(K124) ETC POSITIVE CIRCUIT SHORTED TO BATTERY VOLTAGE







CAUTION: Do not probe the PCM harness connectors. Probing the PCM harness connectors will damage the PCM terminals resulting in poor terminal to pin connection. Install Miller Special Tool #8815 to perform the diagnostics.




Does the test light illuminate brightly?

Yes


No
  • Go To 4

4.(K126) ETC NEGATIVE CIRCUIT SHORTED TO BATTERY VOLTAGE





Does the test light illuminate brightly?

Yes


No
  • Go To 5

5.(K124) ETC POSITIVE CIRCUIT SHORTED TO THE (K126) ETC NEGATIVE CIRCUIT





Is the resistance below 100 ohms?

Yes


No
  • Go To 6

6.(K124) ETC POSITIVE CIRCUIT OPEN






Is the resistance below 5.0 ohms?

Yes
  • Go To 7


No

7.(K124) ETC POSITIVE CIRCUIT SHORTED TO GROUND





Is the resistance below 100 ohms?

Yes


No
  • Go To 8

8.(K126) ETC NEGATIVE CIRCUIT OPEN





Is the resistance below 5.0 ohms?

Yes
  • Go To 9


No

9.(K126) ETC NEGATIVE CIRCUIT SHORTED TO GROUND





Is the resistance below 100 ohms?

Yes


No

10.ETC MOTOR


NOTE: Take the following measurement using special tool #8815 to avoid possible damage to the Throttle Body harness connector.




Is the resistance between 2.5 and 25 ohms at closed throttle?

Yes


No
  • Replace the Throttle Body Assembly. Disconnect the Battery when replacing the Throttle Body Assembly. After installation is complete, use a scan tool and select the ETC RELEARN function.
  • Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)

11.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