P2100-ELECTRONIC THROTTLE CONTROL MOTOR CIRCUITFor 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 CausesTHROTTLE PLATE / BORE INSPECTION(K124) ETC MOTOR (+) CIRCUIT SHORTED TO BATTERY VOLTAGE(K126) ETC MOTOR (-) CIRCUIT SHORTED TO BATTERY VOLTAGE(K124) ETC MOTOR (+) CIRCUIT SHORTED TO THE (K126) ETC MOTOR (-) CIRCUIT(K124) ETC MOTOR (+) CIRCUIT OPEN(K124) ETC MOTOR (+) CIRCUIT SHORTED TO GROUND(K126) ETC MOTOR (-) CIRCUIT OPEN(K126) ETC MOTOR (-) CIRCUIT SHORTED TO GROUNDLOW BATTERY VOLTAGEETC MOTOR/THROTTLE BODYPCM
Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. (Refer to 9 - ENGINE - DIAGNOSIS AND TESTING).Diagnostic Test1.ACTIVE DTCIgnition on, engine not running.When this DTC is Active the engine speed, torque, and vehicle speed are limited to a Limp in mode.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.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.With a scan tool, select View DTCs.View the Freeze Frame data and look closely at the temperatures at which this DTC set.Is the DTC Active at this time?YesGo To 2NoRefer to the INTERMITTENT CONDITION Diagnostic Procedure.Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)2.THROTTLE PLATE INSPECTIONTurn the ignition off.Remove the Air Cleaner Assembly from the Throttle Body.Check for any signs of a foreign material (ice or dirt) on the Throttle Plate or in the bore causing the Throttle Plate to stick.Were any signs of foreign material or scoring of the throttle plate or bore found?YesRemove 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)NoGo To 33.(K124) ETC MOTOR (+) CIRCUIT SHORTED TO BATTERY VOLTAGETurn the ignition off.Disconnect the Throttle Body harness connector.Disconnect the C2 PCM harness connector.Ignition on, engine not running.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.With a 12-volt test light connected to ground, probe the (K124) ETC Motor (+) circuit at the appropriate terminal of special tool #8815.Does the test light illuminate brightly?YesRepair the short to battery voltage on the (K124) ETC Motor (+) circuit.Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)NoGo To 44.(K126) ETC MOTOR (-) CIRCUIT SHORTED TO BATTERY VOLTAGEUsing a 12-volt test light connected to ground, probe the (K126) ETC Motor (-) circuit at the appropriate terminal of special tool #8815.Does the test light illuminate brightly?YesRepair the short to battery voltage in the (K126) ETC Motor (-) circuit.Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)NoGo To 55.(K124) ETC MOTOR (+) CIRCUIT SHORTED TO THE (K126) ETC MOTOR (-) CIRCUITMeasure the resistance between the (K124) ETC Motor (+) circuit and the (K126) ETC Motor (-) circuit at the appropriate terminals of special tool #8815.Is the resistance below 100 ohms?YesRepair the short to between the (K124) ETC Motor (+) circuit and the (K126) ETC Motor (-) circuit.Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)NoGo To 66.(K124) ETC MOTOR (+) CIRCUIT OPENTurn the ignition off.Measure the resistance of the (K124) ETC Motor (+) circuit from the Throttle Body harness connector to the appropriate terminal of special tool #8815.Is the resistance below 5.0 ohms?YesGo To 7NoRepair the open in the (K124) ETC Motor (+) circuit.Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)7.(K124) ETC MOTOR (+) CIRCUIT SHORTED TO GROUNDMeasure the resistance between ground and the (K124) ETC Motor (+) circuit between the appropriate terminals of special tool #8815.Is the resistance below 100 ohms?YesRepair the short to ground in the (K124) ETC Motor (+) circuit.Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)NoGo To 88.(K126) ETC MOTOR (-) CIRCUIT OPENMeasure the resistance of the (K126) ETC Motor (-) circuit from the Throttle Body harness connector to the appropriate terminal of special tool #8815.Is the resistance below 5.0 ohms?YesGo To 9NoRepair the open in the (K126) ETC Motor (-) circuit.Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)9.(K126) ETC MOTOR (-) CIRCUIT SHORTED TO GROUNDMeasure the resistance between ground and the (K126) ETC Motor (-) circuit using the appropriate terminal of special tool #8815.Is the resistance below 100 ohms?YesRepair the short to ground in the (K126) ETC Motor (-) circuit.Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)NoGo To 1010.ETC MOTORTake the following measurement using special tool #8815 to avoid possible damage to the Throttle Body harness connector.Measure the resistance of the ETC Motor between the (K124) ETC Motor (+) circuit and the (K126) ETC Motor (-) circuit at the appropriate terminals of special tool #8815.Is the resistance between 2.5 and 25 ohms at closed throttle?YesGo To 11NoReplace 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.PCMBefore continuing, check the PCM harness connector terminals for corrosion, damage, or terminal push out. Repair as necessary.Using the schematics as a guide, inspect the wire harness and connectors. Pay particular attention to all Power and Ground circuits.Were there any problems found?YesRepair as necessary.Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)NoReplace and program the Powertrain Control Module per Service Information.Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)