Dodge Ram Truck 1500-2500-3500. Manual — part 995

P2138-ACCELERATOR PEDAL POSITION SENSOR 1/2 CORRELATION (CONTINUED)

For the Engine circuit diagram (Refer to 9 - ENGINE - SCHEMATICS AND DIAGRAMS).

For a complete wiring diagram Refer to Section 8W.

•

When Monitored:
With the ignition on and no APPS No.1 and APPS No.2 DTC present.

•

Set Condition:
APPS values No.1 and No.2 are not coherent. Idle is additionally forced when the brake pedal is pressed or
failed. Acceleration rate and Engine output are limited. One trip fault and the code will set within 5 seconds.
ETC light is flashing.

Possible Causes

EXCESSIVE RESISTANCE IN THE (F855) 5-VOLT SUPPLY CIRCUIT

EXCESSIVE RESISTANCE IN THE (F856) 5-VOLT SUPPLY CIRCUIT

EXCESSIVE RESISTANCE IN THE (K167) SENSOR NO.1 RETURN CIRCUIT

EXCESSIVE RESISTANCE IN THE (K400) SENSOR NO.2 RETURN CIRCUIT

EXCESSIVE RESISTANCE IN THE (K23) APP SENSOR NO.1 SIGNAL CIRCUIT

EXCESSIVE RESISTANCE IN THE (K29) APP SENSOR NO.2 SIGNAL CIRCUIT

APP SENSOR

PCM

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

Diagnostic Test

1.

ACTIVE DTC

Ignition on, engine not running.

With a scan tool, read DTCs.

NOTE: Repair any other 5-Volt Supply or APPS High and Low DTCs before diagnosing P2138.

Is the DTC active at this time?

Yes

>> Go To 2

No

>> Refer to the INTERMITTENT CONDITION Diagnostic Procedure.

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

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ENGINE - ELECTRICAL DIAGNOSTICS - 3.7L/4.7L/5.7L

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P2138-ACCELERATOR PEDAL POSITION SENSOR 1/2 CORRELATION (CONTINUED)

2.

EXCESSIVE RESISTANCE IN THE (K23) APPS NO.1 SIGNAL CIRCUIT

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 diagnosis.
Turn the ignition off.

Disconnect the C3 PCM harness connector.

Disconnect the APP Sensor harness connector.

Measure the resistance of (K23) APP Sensor No.1 Signal circuit from
the APP Sensor harness connector to the appropriate terminals of
special tool #8815.

Is the resistance below 5.0 ohms?

Yes

>> Go To 3

No

>> Repair the excessive resistance in the (K23) APP Sensor

No.1 Signal circuit.

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

3.

EXCESSIVE RESISTANCE IN THE (K29) APPS NO.2 SIGNAL
CIRCUIT

Measure the resistance of (K29) APPS No.2 Signal circuit from the
APP Sensor harness connector to the appropriate terminals of special
tool #8815.

Is the resistance below 5.0 ohms?

Yes

>> Go To 4

No

>> Repair the excessive resistance in the (K29) APP Sensor

No.2 Signal circuit.

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

DR/DH

ENGINE - ELECTRICAL DIAGNOSTICS - 3.7L/4.7L/5.7L

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P2138-ACCELERATOR PEDAL POSITION SENSOR 1/2 CORRELATION (CONTINUED)

4.

EXCESSIVE RESISTANCE IN THE (F855) 5-VOLT SUPPLY CIRCUIT

Disconnect the C2 PCM harness connector.

Measure the resistance of the (F855) 5-volt Supply circuit from the
APP Sensor harness connector to the appropriate terminal of special
tool #8815.

Is the resistance above 5.0 ohms?

Yes

>> Repair the excessive resistance in the (F855) 5-volt Sup-

ply circuit.

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

No

>> Go To 5

5.

EXCESSIVE RESISTANCE IN THE (F856) 5-VOLT SUPPLY
CIRCUIT

Disconnect the C1 PCM harness connector.

Measure the resistance of the (F856) 5-volt Supply circuit from the
APP Sensor harness connector to the appropriate terminal of special
tool #8815.

Is the resistance above 5.0 ohms?

Yes

>> Repair the excessive resistance in the (F856) 5-volt Sup-

ply circuit.

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

No

>> Go To 6

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ENGINE - ELECTRICAL DIAGNOSTICS - 3.7L/4.7L/5.7L

DR/DH

P2138-ACCELERATOR PEDAL POSITION SENSOR 1/2 CORRELATION (CONTINUED)

6.

EXCESSIVE RESISTANCE IN THE (K167) SENSOR NO.1
RETURN CIRCUIT

Measure the resistance of the (K167) APP Sensor No.1 Return circuit
from the APP Sensor harness connector to the appropriate terminal of
special tool #8815.

Is the resistance above 5.0 ohms?

Yes

>> Repair the excessive resistance in the (K167) Sensor No.1

Return circuit.

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

No

>> Go To 7

7.

EXCESSIVE RESISTANCE IN THE (K400) SENSOR NO.2 RETURN CIRCUIT

Measure the resistance of the (K400) APP Sensor No.2 Return circuit
from the APP Sensor harness connector to the appropriate terminal
special tool #8815.

Is the resistance above 5.0 ohms?

Yes

>> Repair the excessive resistance in the (K400) Sensor No.2

Return circuit.

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

No

>> Go To 8

DR/DH

ENGINE - ELECTRICAL DIAGNOSTICS - 3.7L/4.7L/5.7L

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