DU: Intake Air Temperature 2 (IAT2)

DU: Introduction See: DU: Intake Air Temperature 2 (IAT2) - Introduction

DU10 DTC P1115: SIMULATE OPPOSITE SIGNAL TO PCM

• With IAT2 temperature sensor disconnected, connect a jumper wire between the sensor signal and SIG RTN circuits at the temperature sensor harness connector.
• Key on.

Note: If a scan tool communication concern exists, remove jumper wire immediately and GO to DU12.

• Access IAT2 temperature sensor voltage PID.

Is the IAT2 temperature sensor voltage PID less than 0.2 volts?
Yes

• REPLACE suspect sensor.

No

• KEY OFF. REMOVE jumper wire. GO to DU11

.

DU11 CHECK TEMPERATURE SENSOR SIGNAL AND SIG RTN CIRCUITS FOR OPEN IN HARNESS

Note: Refer to the PCM connector pin numbers on this pinpoint test cover page.

• Disconnect PCM.
• Measure resistance of sensor signal circuit between PCM harness connector pin and IAT2 sensor harness connector.
• Measure resistance of SIG RTN circuit between PCM harness connector pin and IAT2 temperature sensor harness connector.

Is each resistance less than 5.0 ohms?
Yes

• REPLACE PCM (refer to Section 2, Flash Electrically Erasable Programmable Read Only Memory (EEPROM) See: Programming and Relearning\Flash Electrically Eraseable Programmable Read Only Memory - Flash EEPROM).

No

• REPAIR open circuits.

DU12 CHECK TEMPERATURE SIGNAL FOR SHORT TO VREF IN HARNESS

• Key off.
• Disconnect PCM.
• Measure resistance between IAT2 temperature signal circuit at the sensor harness connector and VREF circuits at the PCM harness connector.

Is the resistance greater than 10,000 ohms?
Yes

• REPLACE PCM (refer to Section 2, Flash Electrically Erasable Programmable Read Only Memory (EEPROM) See: Programming and Relearning\Flash Electrically Eraseable Programmable Read Only Memory - Flash EEPROM).

No

• REPAIR short to VREF.

DU20 P1114: SIMULATE OPPOSITE SIGNAL TO PCM

• Disconnect harness from IAT2 temperature sensor.
• Connect scan tool.
• Key on.
• Access IAT2 temperature sensor voltage PID.
• Key off.

Is the IAT2 temperature sensor voltage PID greater than 4.2 volts?
Yes

• REPLACE sensor.

No

• GO to DU21

.

DU21 CHECK VREF VOLTAGE TO TP SENSOR

• Refer to schematic at the beginning of the pinpoint test.
• Disconnect TP sensor.
• Key on, engine off.
• Measure the voltage between VREF and SIG RTN circuits at the TP sensor harness connector.

Is voltage between 4.0 and 6.0 volts?
Yes

• There is sufficient VREF voltage. RECONNECT TP sensor. GO to DU22

0. KEY OFF.

No

• GO to C1 See: C: Reference Voltage - Pinpoint Test

.

DU22 CHECK TEMPERATURE SIGNAL CIRCUIT FOR SHORT TO GROUND IN HARNESS

Note: Refer to the PCM connector pin numbers on this pinpoint test cover page.

• Disconnect PCM.
• Measure resistance between sensor signal and SIG RTN circuits and then between sensor signal and PWR GND circuits at the PCM harness connector.

Is each resistance greater than 10,000 ohms?
Yes

• REPLACE PCM (refer to Section 2, Flash Electrically Erasable Programmable Read Only Memory (EEPROM) See: Programming and Relearning\Flash Electrically Eraseable Programmable Read Only Memory - Flash EEPROM).

No

• REPAIR short circuit.

DU30 P0127 IAT2 TOO HIGH. CHECK SUPERCHARGER INTERCOOLER PUMP OPERATION

• Connect scan tool.
• Access Output Test Mode.
• Select Mode: ALL ON.
• Command pump to run.

Does supercharger intercooler pump run?
Yes

• GO to DU31

.

No

• KEY OFF. GO to KP1 See: KP: Charge Air Cooler Pump (CAC) - Pinpoint Test

(Charge Air Cooler Pump).

DU31 CHECK INTERCOOLER SYSTEM

• Check intercooler system for:
• low fluid level.
• cracked coolant lines.
• blocked heat exchanger or coolant lines.
• crossed coolant lines.

Is intercooler system OK?
Yes

• KEY OFF. GO to DU32

.

No

• REPAIR as necessary.

DU32 SIMULATE HIGH IAT2 VOLTAGE SIGNAL

• Connect scan tool.
• Key on.
• Access IAT2 VPID.
• Observe PID while disconnecting IAT2 sensor.

Is PID greater than 4.0V?
Yes

• GO to DU33

.

No

• REPLACE PCM (refer to Section 2, Flash Electrically Erasable Programmable Read Only Memory (EEPROM) See: Programming and Relearning\Flash Electrically Eraseable Programmable Read Only Memory - Flash EEPROM).

DU33 SIMULATE LOW IAT2 VOLTAGE SIGNAL

• Access IAT2 VPID.
• Observe PID while connecting a jumper wire between the sensor signal and SIG RTN circuit at the temperature sensor harness connector.

Is PID less than 1.0V?
Yes

• RECONNECT sensor and GO to Section 6 See: Diagnostic Trouble Code Tests and Associated Procedures\SECTION 6: Reference Values

, Reference Values. COMPARE IAT2 PID to reference values under the given
road test conditions. If sensor is not in range, REPLACE IAT2 sensor.

No

• REPLACE PCM (refer to Section 2, Flash Electrically Erasable Programmable Read Only Memory (EEPROM) See: Programming and Relearning\Flash Electrically Eraseable Programmable Read Only Memory - Flash EEPROM).