P0113 INTAKE AIR TEMPERATURE (IAT) SENSOR VOLTAGE TOO HIGH

When Monitored and Set Condition:

When Monitored: With ignition on and battery voltage greater than 10.4 volts.
Set Condition: The circuit voltage to the ECM is above a calibrated threshold for a certain period of time.

POSSIBLE CAUSES

• FAILED SENSOR
• INTERMITTENT CONDITION
• (K21) SENSOR SIGNAL CIRCUIT OPEN
• (K55) RETURN CIRCUIT OPEN
• SHORT IN HARNESS
• ECM

DIAGNOSTIC PROCEDURE

NOTE: Refer to VERIFICATION TESTS for appropriate verification test procedures.

1. Turn the ignition off. Disconnect the IAT sensor harness connector. Check connectors - Clean/repair as necessary. Measure the resistance of the IAT sensor. Is the resistance between 300 and 90k ohms?
   Yes --> Go To 2
   No --> Replace the Intake Air Temperature Sensor/map sensor. Perform POWERTRAIN VERIFICATION TEST VER - 1 (DIESEL).
2. Reconnect the IAT harness connector. Turn the ignition on. With the DRBIII®, erase DTCs. With the DRBIII®, read DTCs. Is P0113 still set?
   Yes --> Go To 3
   No --> Refer to the SYMPTOM: INTERMITTENT CONDITION Symptom (Diagnostic Procedure). Perform POWERTRAIN VERIFICATION TEST VER - 1 (DIESEL).
3. Turn the ignition off. Disconnect the ECM harness connector(s). Measure the resistance between the temperature sensor (K21) signal and (K55) return circuit at the ECM harness connector with the sensor connected Is the resistance between 300 and 90k ohms?
   Yes --> Go To 6
   No --> Go To 4
4. Measure the resistance of the sensor (K21) signal circuit between the sensor harness connector and the ECM harness connector. Is the resistance less than 10 Ohms?
   Yes --> Go To 5
   No --> Repair the open Sensor (K21) signal circuit or the harness. Perform POWERTRAIN VERIFICATION TEST VER - 1 (DIESEL).
5. Measure the resistance of the sensor (K55) Return circuit between the sensor harness connector and the ECM harness connector. Is the resistance less than 10 Ohms?
   Yes --> Go To 6
   No --> Repair the open (K55) return circuit or the harness. Perform POWERTRAIN VERIFICATION TEST VER - 1 (DIESEL).
6. Check for a short circuit from (K21) signal circuit to all other circuits at the ECM harness connector. Is the resistance more than 100 k ohms?
   Yes --> Go To 7
   No --> Repair the short in the wiring harness or replace the harness. Perform POWERTRAIN VERIFICATION TEST VER - 1 (DIESEL).
7. Reconnect the ECM harness connectors. Turn the ignition on. With the DRBIII®, erase DTCs. While monitoring with DRBIII®, use a jumper wire and connect the sensor (K21) signal circuit to the sensor (K55) return circuit at the sensor harness connector. Did the DTC P0112 set?
   Yes --> Refer to the SYMPTOM: INTERMITTENT CONDITION Symptom (Diagnostic Procedure). Perform POWERTRAIN VERIFICATION TEST VER - 1 (DIESEL).
   No --> Replace the ECM. Perform POWERTRAIN VERIFICATION TEST VER - 1 (DIESEL).