Dodge Ram Truck 1500-2500-3500. Manual — part 1162

P0131-O2 SENSOR 1/1 CIRCUIT VOLTAGE TOO LOW

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ENGINE - ELECTRICAL DIAGNOSTICS - SRT-10

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P0131-O2 SENSOR 1/1 CIRCUIT VOLTAGE TOO LOW (CONTINUED)

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

For a complete wiring diagram Refer to Section 8W.

•

When Monitored:
At a cold start, engine coolant below 98°F, Ambient/Battery Sensor reading within 27°F, and Engine Coolant
Temperature above 170°F on the previous key off.

•

Set Condition:
The Oxygen Sensor signal voltage is below 0.156 of a volt for 28 seconds after starting engine.

Possible Causes

(K41) O2 1/1 SIGNAL CIRCUIT SHORTED TO GROUND

(K41) O2 1/1 SIGNAL CIRCUIT SHORTED TO THE (K900) SENSOR GROUND CIRCUIT

O2 SENSOR

PCM

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

Diagnostic Test

1.

O2 SENSOR BELOW 0.16 OF A VOLT

Ignition on, engine not running.

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

Start the engine.

Allow the engine to idle for 4 to 5 minutes.

With the scan tool, read the O2 Sensor voltage.

Is the voltage below 0.16 of a volt?

Yes

>> Go To 2

No

>> Refer to the INTERMITTENT CONDITION Diagnostic Procedure.

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

2.

O2 SENSOR OPERATION

WARNING: When the engine is operating, do not stand in a direct line with the fan. Do not put your hands
near the pulleys, belts, or fan. Do no wear loose clothing.
Disconnect the O2 Sensor harness connector.

Start the engine.

With the scan tool, monitor the O2 Sensor voltage.

Is the O2 Sensor voltage above 0.16 of a volt?

Yes

>> Replace the O2 Sensor.

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

No

>> Go To 3

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ENGINE - ELECTRICAL DIAGNOSTICS - SRT-10

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P0131-O2 SENSOR 1/1 CIRCUIT VOLTAGE TOO LOW (CONTINUED)

3.

(K41) O2 SENSOR 1/1 SIGNAL CIRCUIT SHORTED TO GROUND

Turn the ignition off.

Disconnect the C1 PCM harness connector.

Measure the resistance between ground and the (K41) O2 Sensor 1/1
Signal circuit at the 1/1 O2 Sensor harness connector.

Is the resistance below 100 ohms?

Yes

>> Repair the short to ground in the (K41) O2 Sensor 1/1Sig-

nal circuit.

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

No

>> Go To 4

4.

(K41) O2 SENSOR 1/1 SIGNAL CIRCUIT SHORTED TO (K900) SENSOR GROUND CIRCUIT

Measure the resistance between the (K41) O2 Sensor 1/1 Signal cir-
cuit and the (K900) Sensor ground circuit at the 1/1 O2 Sensor har-
ness connector.

Is the resistance below 100 ohms?

Yes

>> Repair the short between the (K900) Sensor ground circuit

and the (K41) O2 Sensor 1/1 Signal circuit.

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

No

>> Go To 5

5.

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.

Were there any problems found?

Yes

>> Repair as necessary.

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

No

>> Replace and program the Powertrain Control Module per Service Information.

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

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ENGINE - ELECTRICAL DIAGNOSTICS - SRT-10

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P0132-O2 SENSOR 1/1 CIRCUIT VOLTAGE TOO HIGH

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ENGINE - ELECTRICAL DIAGNOSTICS - SRT-10

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