Dodge Ram Truck 1500-2500-3500. Manual — part 973

P2096-DOWNSTREAM FUEL TRIM SYSTEM 1 LEAN (CONTINUED)

6.

(K299) O2 SENSOR 1/2 HEATER CONTROL CIRCUIT SHORTED TO GROUND

Turn the ignition off.

Disconnect the C3 PCM harness connector.

Measure the resistance between ground and the (K299) O2 Sensor
1/2 Heater Control circuit from the O2 Sensor harness connector.

Is the resistance below 5.0 ohms?

Yes

>> Repair the short to ground in the (K299) O2 Sensor 1/2

Heater Control circuit.

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

No

>> Go To 7

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

DR/DH

P2096-DOWNSTREAM FUEL TRIM SYSTEM 1 LEAN (CONTINUED)

7.

(K904) O2 RETURN DOWNSTREAM CIRCUIT

Measure the voltage on the (K904) O2 Return Downstream circuit in
the O2 Sensor harness connector.

Is the voltage at 2.5 volts?

Yes

>> Check the fuel system for contaminants.

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

No

>> Check the (K904) O2 Return Downstream circuit for a

short to ground, open, or short to voltage. Inspect the O2
Sensor connector and the PCM harness connector. If OK,
replace and program the Powertrain Control Module per
Service Information.

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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P2097-DOWNSTREAM FUEL TRIM SYSTEM 1 RICH

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

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P2097-DOWNSTREAM FUEL TRIM SYSTEM 1 RICH (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 engine running in closed loop mode, the ambient/battery temperature above (-7°) 20°F, altitude below
8500 ft.

•

Set Condition:
If the PCM multiplies short term compensation by long term adaptive as well as a purge fuel multiplier and the
result is below a certain value for 30 seconds over two trips, a freeze frame is stored, the MIL illuminates and
a trouble code is stored. Two Trip Fault. Three good trips to turn off the MIL.

Possible Causes

EXHAUST LEAK

ENGINE MECHANICAL

1/2 O2 SENSOR

(K141) O2 SENSOR 1/2 SIGNAL CIRCUIT

(K299) O2 HEATER 1/2 CONTROL CIRCUIT

(K904) O2 RETURN DOWNSTREAM CIRCUIT

FUEL CONTAMINATION

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

Diagnostic Test

1.

ACTIVE DTC

NOTE: Check the vehicle repair history. If the 1/2 O2 has been replaced make sure that the O2 sensor was
properly installed and meets OEM specification.

NOTE: Check for contaminants that may have damaged the O2 Sensor: contaminated fuel, unapproved sil-
icone, oil and coolant.
Ignition on, engine not running.

With a scan tool, read DTCs.

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)

DR/DH

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

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