Dodge Ram Truck 1500-2500-3500. Manual — part 378

*BRAKE WARNING INDICATOR ALWAYS ON (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

(B20) BRAKE FLUID LEVEL SENSOR SENSE CIRCUIT SHORT TO GROUND

(B25) PARK BRAKE SWITCH SENSE CIRCUIT SHORT TO GROUND

BRAKE FLUID LEVEL SENSOR

PARK BRAKE SWITCH

ANTI-LOCK BRAKES MODULE

INSTRUMENT CLUSTER

Diagnostic Test

1.

BRAKE FLUID LEVEL SENSOR

NOTE: Diagnose and repair any MIC, Brake, or Communication
DTCs before proceeding with this test.
Disconnect the Brake Fluid Level Sensor harness connector.

Measure the resistance of the Brake Fluid Level Sensor between pin 1
and pin 2.

Does the resistance measure less than 900 ohms?

Yes

>> Replace the Brake Fluid Level Sensor in accordance with

the Service Information.

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

No

>> Go To 2

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INSTRUMENT CLUSTER - ELECTRICAL DIAGNOSTICS

DR/DH

*BRAKE WARNING INDICATOR ALWAYS ON (CONTINUED)

2.

(B20) BRAKE FLUID LEVEL SENSOR SENSE CIRCUIT SHORT TO GROUND

Turn the ignition off.

Disconnect the Brake Fluid Level Sensor harness connector.

Disconnect the Anti-lock Brakes Module harness connector.

Measure the resistance between ground and the (B20) Brake Fluid
Level Sensor Sense circuit.

Is the resistance below 5.0 ohms?

Yes

>> Repair the (B20) Brake Fluid Level Sensor Sense circuit

for a short to ground.

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

No

>> Go To 3

3.

PARK BRAKE SWITCH

Turn the ignition off.

Disconnect the Park Brake Switch harness connector.

Turn the ignition on.

Observe the Brake warning indicator.

Did the Brake warning indicator illuminate briefly and then turn
off?

Yes

>> Replace the Park Brake Switch in accordance with the

Service Information.

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

No

>> Go To 4

DR/DH

INSTRUMENT CLUSTER - ELECTRICAL DIAGNOSTICS

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*BRAKE WARNING INDICATOR ALWAYS ON (CONTINUED)

4.

(B25) PARK BRAKE SWITCH SENSE CIRCUIT SHORT TO GROUND

Turn the ignition off.

Disconnect the Park Brake Switch harness connector.

Disconnect the Instrument Cluster C3 harness connector.

Measure the resistance between ground and the (B25) Park Brake
Switch Sense circuit.

Is the resistance below 5.0 ohms?

Yes

>> Repair the (B25) Park Brake Switch Sense circuit for a

short to ground.

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

No

>> Go To 5

5.

ANTI-LOCK BRAKES MODULE

Turn the ignition off.

Reconnect any harness connector(s) that were previously disconnected.

Turn the ignition on.

With the DRBIII

T

in Inputs/Outputs, read the Brake Fluid Level Sensor state.

Does the DRBIII

T

display

(

Closed

(

?

Yes

>> Replace the Anti-lock Brakes Module in accordance with the Service Information.

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

DR/DH

*BRAKE WARNING INDICATOR INOPERATIVE

DR/DH

INSTRUMENT CLUSTER - ELECTRICAL DIAGNOSTICS

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