Dodge Ram Truck 1500-2500-3500. Manual — part 380

*FUEL GAUGE INACCURATE

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INSTRUMENT CLUSTER - ELECTRICAL DIAGNOSTICS

DR/DH

*FUEL GAUGE INACCURATE (CONTINUED)

For the Instrument Cluster circuit diagram (Refer to 8 - ELECTRICAL/INSTRUMENT CLUSTER - SCHEMATICS
AND DIAGRAMS).

For a complete wiring diagram Refer to Section 8W.

Possible Causes

FUEL LEVEL SENSOR WIRING

INSTRUMENT CLUSTER

Diagnostic Test

1.

DTC PRESENT

NOTE: Diagnose and repair any PCI Bus problems before proceeding with this test.
Turn the ignition on.

With the DRBIII

T

, read the PCM DTCs.

Does the DRBIII

T

display any Fuel Level Sensor related DTC?

Yes

>> Refer to the Powertrain Diagnostic Information for the related symptom(s).

Perform (NGC) POWERTRAIN VERIFICATION TEST VER - 5.

No

>> Go To 2

2.

INSTRUMENT CLUSTER

Perform the Instrument Cluster Self Test as follows:

Turn the ignition off.

Press and hold the Trip/Reset button.

Turn the ignition on.

Observe the Fuel Gauge during the Self Test.

The Fuel Gauge pointer should pause at each of these following positions: E, 1/4, 1/2, 3/4, Full, and back to E.

Does the Fuel Gauge function as described above?

Yes

>> Go To 3

No

>> Replace the Instrument Cluster in accordance with the Service Information.

Perform BODY VERIFICATION TEST - VER 1. (Refer to BODY VERIFICATION TEST - VER 1.)

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INSTRUMENT CLUSTER - ELECTRICAL DIAGNOSTICS

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*FUEL GAUGE INACCURATE (CONTINUED)

3.

FUEL LEVEL SENSOR WIRING

Turn the ignition off.

Disconnect the Fuel Pump Module harness connector.

Disconnect the PCM C2 and C3 harness connectors.

Measure the resistance of the (N4) Fuel Level Sensor Signal circuit
between the Fuel Pump Module harness connector and the PCM har-
ness connector.

Measure the resistance of the (K900) Sensor Ground circuit between
the Fuel Pump Module harness connector and the PCM harness con-
nector.

Is the resistance below 5.0 ohms on both circuits.

Yes

>> Replace the Fuel Level Sensor in accordance with the

Service Information.

Perform BODY VERIFICATION TEST - VER 1. (Refer to
BODY VERIFICATION TEST - VER 1.)

No

>> Repair the circuits with a resistance above 5.0 ohms for

an open.

Perform BODY VERIFICATION TEST - VER 1. (Refer to
BODY VERIFICATION TEST - VER 1.)

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INSTRUMENT CLUSTER - ELECTRICAL DIAGNOSTICS

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*ONE GAUGE INOPERATIVE - GAS ENGINES

For a complete wiring diagram Refer to Section 8W.

Possible Causes

POWERTRAIN CONTROL MODULE

INSTRUMENT CLUSTER

Diagnostic Test

1.

POWERTRAIN CONTROL MODULE

Turn the ignition on.

With the DRBIII

T

, read DTCs.

Does the DRBIII

T

display any PCM DTCs?

Yes

>> Refer to the DRIVEABILITY category and perform the appropriate symptom.

Perform BODY VERIFICATION TEST - VER 1. (Refer to BODY VERIFICATION TEST - VER 1.)

No

>> Go To 2

2.

INSTRUMENT CLUSTER

Turn the ignition off.

Perform the Instrument Cluster Self Test.

NOTE: NOTE: The Self Test can be initiated manually by depressing and holding the Trip Reset button while
turning the ignition on, or by using the DRBIII

T

.

Observe the gauge in question while the Instrument Cluster performs the Self Test.

The gauges should position at the following calibrations points:

Speedometer MPH: 0, 20, 60, 90

Tachometer Gas: 0, 1000, 3000, 6000

Fuel: E, 1/4, 1/2, 3/4, F

Coolant: Cold, 1/4, 1/2, 3/4, HI

Volts: 6, 9, 12, 15, 17

Did the gauge in question operate properly?

Yes

>> The condition is not present at this time. Monitor DRBIII

T

parameters while wiggling the related wire

harness. Refer to any Technical Service Bulletins (TSB) that may apply. Visually inspect the related wir-
ing harness and connector terminals.

Perform BODY VERIFICATION TEST - VER 1. (Refer to BODY VERIFICATION TEST - VER 1.)

No

>> Replace and configure the Instrument Cluster in accordance with the Service Information.

Perform BODY VERIFICATION TEST - VER 1. (Refer to BODY VERIFICATION TEST - VER 1.)

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INSTRUMENT CLUSTER - ELECTRICAL DIAGNOSTICS

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