Dodge Ram Truck 1500-2500-3500. Manual — part 1151

P0111-INTAKE AIR TEMP PERFORMANCE

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ENGINE - ELECTRICAL DIAGNOSTICS - SRT-10

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P0111-INTAKE AIR TEMP PERFORMANCE (CONTINUED)

For the Engine circuit diagram (Refer to 8 - ELECTRICAL/ELECTRONIC CONTROL MODULES/ENGINE CON-
TROL MODULE - SCHEMATIC - ELECTRICAL)

For a complete wiring diagram Refer to Section 8W.

•

When Monitored:
With the ignition on and no Intake Air Temperature Sensor open/shorted faults present.

•

Set Condition:
After 5 warm cycles have occurred (coolant increases at least 22°C (40°F) to a minimum of 71°C (160°F) and
the odometer mileage has increased 196.6 miles and the Intake Air Temperature has had less than 5°C (9°F)
change in temperature.

Possible Causes

RESISTANCE IN THE (K21) IAT SENSOR SIGNAL CIRCUIT

RESISTANCE IN THE (K900) SENSOR GROUND CIRCUIT

IAT SENSOR

PCM

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

1.

GOOD TRIP EQUAL TO ZERO

Ignition on, engine not running.

With the scan tool, read DTCs and record the related Freeze Frame data.

Is the Good Trip Counter equal to zero?

Yes

>> Go To 2

No

>> Refer to the INTERMITTENT CONDITION Diagnostic Procedure. (Refer to 9 - ENGINE - DIAGNOSIS

AND TESTING)

2.

IAT SENSOR VOLTAGE ABOVE 4.6 VOLTS

Turn the ignition off.

Disconnect the Intake Air Temperature Sensor harness connector.

Ignition on, engine not running.

With the scan tool, read the IAT voltage.

Is the voltage above 4.6 volts?

Yes

>> Go To 3

No

>> Go To 5

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ENGINE - ELECTRICAL DIAGNOSTICS - SRT-10

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P0111-INTAKE AIR TEMP PERFORMANCE (CONTINUED)

3.

IAT SENSOR VOLTAGE BELOW 1.0 VOLT

Turn the ignition off.

Connect a jumper wire across the IAT Sensor harness connector.

Ignition on, engine not running.

With the scan tool, read the IAT voltage.

Is the voltage below 1.0 volt?

Yes

>> Replace the Intake Air Temperature Sensor.

Perform POWERTRAIN VERIFICATION TEST. (Refer to 9
- ENGINE - STANDARD PROCEDURE)

No

>> Go To 4

NOTE: Remove the jumper wire and connect the Sensor harness
connector before continuing.

4.

RESISTANCE IN THE (K21) IAT SENSOR SIGNAL CIRCUIT

Turn the ignition off.

NOTE: Make sure the voltmeter leads meet the terminals in the
connector and that there is good terminal to wire connection.

NOTE: Make sure the voltmeter leads are connected for positive
polarity
Backprobe the (K21) IAT Sensor Signal circuit at the IAT Sensor har-
ness connector and PCM harness connector with the voltmeter leads.

Start the engine.

Allow the engine to idle.

Is the voltage below 0.10 of a volt?

Yes

>> Go To 6

No

>> Repair the excessive resistance in the (K21) IAT Sensor

Signal circuit.

Perform POWERTRAIN VERIFICATION TEST. (Refer to 9
- ENGINE - STANDARD PROCEDURE)

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ENGINE - ELECTRICAL DIAGNOSTICS - SRT-10

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P0111-INTAKE AIR TEMP PERFORMANCE (CONTINUED)

5.

RESISTANCE IN THE (K900) SENSOR GROUND CIRCUIT

Turn the ignition off.

NOTE: Make sure the voltmeter leads meet the terminals in the
connector and that there is good terminal to wire connection.

NOTE: Make sure the voltmeter leads are connected for positive
polarity
Backprobe the (K900) Sensor ground circuit at the IAT Sensor harness
connector and PCM harness connector with both leads of a voltmeter.

Start the engine.

Allow the engine to idle.

Is the voltage below 0.10 of a volt?

Yes

>> Go To 6

No

>> Repair the excessive resistance in the (K900) Sensor

ground circuit.

Perform POWERTRAIN VERIFICATION TEST. (Refer to 9
- ENGINE - STANDARD PROCEDURE)

NOTE: Turn the ignition off before continuing.

6.

PCM

NOTE: Before 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.

If there are no possible causes remaining, view repair.

Repair

Replace and program the Powertrain Control Module per Service Information.

Perform POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)

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