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Jeep Wrangler TJ. Manual - part 38

Symptom:

*AXLE LOCK INDICATOR PROBLEMS

POSSIBLE CAUSES

DTC PRESENT

AXLE LOCKER SWITCH FUSED B(+) CIRCUIT OPEN

AXLE LOCKER SWITCH GROUND CIRCUIT OPEN

FRONT LOCKER REQUEST CIRCUIT OPEN

REAR LOCKER REQUEST CIRCUIT OPEN

AXLE LOCK SWITCH

INTERMITTENT CONDITION

INSTRUMENT CLUSTER

TEST

ACTION

APPLICABILITY

NOTE: The following tests are to diagnose an inoperative Axle Lock indica-
tor. If the Axle Lock indicator flashes, the Enable conditions have not been
met to lock the axle, or an axle mechanical fault exists.
NOTE: The Front Axle Lock and Rear Axle Lock indicators can NOT be
diagnosed using the Instrument Cluster self test.
With the DRBIII

t, read DTCs.

Are any ABS, PCM, VSS, or Transfer Case DTCs present?

All

Yes

→ Refer to DRIVEABILITY or TRANSMISSION/TRANSFER CASE

information for the related symptom(s).
Perform BODY VERIFICATION TEST - VER 1.

→ Go To 2

Select the inoperative indicator.

All

Rear Axle Lock Indicator

Go To

Front Axle Lock Indicator

Go To

Perform the Axle Locker test.
Turn the ignition on.
Place transfer case in 4WD Lo and visually confirm by observing the 4WD indicator.
Drive the vehicle at less than 10 MPH (16 km/h).
Press the Axle Lock switch once.
Did the Rear Axle Lock indicator illuminate?

All

Yes

→ The condition is not present at this time. Monitor DRBIIIt

parameters while wiggling the related wire harness. Refer to any
Technical Service Bulletins(TSB) that may apply. Visually inspect
the related wiring harness and connector terminals.
Perform BODY VERIFICATION TEST - VER 1.

→ Go To 4

149

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TEST

ACTION

APPLICABILITY

Place the transfer case in 4WD Lo.
Drive the vehicle at less than 2.5 MPH (4 km/h).
With the DRBIII

t in Inputs/Outputs, read the Enable 1 state, (should read LOW).

With the DRBIII

t in Inputs/Outputs, read the Rear Lock Request state.

Press the Axle Lock switch once.
Did the Rear Lock Request change state?

All

Yes

→ Replace and configure the Instrument Cluster in accordance with

the Service Information.
Perform BODY VERIFICATION TEST - VER 1.

→ Go To 5

Turn the ignition off.
Disconnect the Axle Lock Switch harness connector.
Measure the voltage between the Fused B(+) circuit and ground.
Is the voltage below 10.5 volts?

All

Yes

→ Repair the Axle Locker Switch Fused B(+) circuit for an open.

Perform BODY VERIFICATION TEST - VER 1.

→ Go To 6

Turn the ignition off.
Disconnect the Axle Lock Switch harness connector.
Measure the resistance between ground and the Axle Locker Switch Ground circuit.
Is the resistance above 5.0 ohms?

All

Yes

→ Repair the Axle Locker Switch Ground circuit for an open.

Perform BODY VERIFICATION TEST - VER 1.

→ Go To 7

Turn the ignition off.
Disconnect the Axle Locker Switch harness connector.
Disconnect the Instrument Cluster C1 harness connector.
Measure the resistance of the Rear Locker Request circuit between the Axle Locker
Switch connector and the Instrument Cluster C1 connector.
Is the resistance above 5.0 ohms?

All

Yes

→ Repair the Rear Locker Request circuit for an open.

Perform BODY VERIFICATION TEST - VER 1.

→ Replace the Axle Lock Switch in accordance with the Service

Information.
Perform BODY VERIFICATION TEST - VER 1.

150

INSTRUMENT CLUSTER

*AXLE LOCK INDICATOR PROBLEMS —

Continued

TEST

ACTION

APPLICABILITY

Place transfer case in 4WD Lo and drive vehicle at less than 2.5 MPH (4 km/h).
Press the Axle Locker Switch once to lock the rear axle.
With the DRBIII

t in Inputs/Outputs, ensure that the Enable 1 and Enable 2 states

both read LOW.
With the DRBIII

t in Inputs/Outputs, ensure that the Rear Lock Request and Rear

Lock Return states both read LOCKED.
Press the Axle Locker Switch again.
Did the Front Axle Lock indicator illuminate?

All

Yes

→ The condition is not present at this time. Monitor DRBIIIt

→ Go To 9

Place the vehicle in 4WD Lo, operate vehicle at 2.5 MPH (4 km/h) or less.
With the DRBIII

t in Inputs/Outputs, ensure that the Enable 1 and Enable 2 states

read LOW.
The Rear Axle Lock indicator must be illuminated.
With the DRBIII

t in Inputs/Outputs, read the Front Lock Request state.

Press the Axle Locker Switch.
Did the Front Axle Lock Request change state?

All

Yes

→ Replace and configure the Instrument Cluster in accordance with

the Service Information.
Perform BODY VERIFICATION TEST - VER 1.

→ Go To 10

Turn the ignition off.
Disconnect the Axle Locker Switch harness connector.
Disconnect the Instrument Cluster C2 harness connector.
Measure the resistance of the Front Locker Request circuit between the Axle Locker
Switch connector and the Instrument Cluster C2 connector.
Is the resistance above 5.0 ohms?

All

Yes

→ Repair the Front Locker Request circuit for an open.

Perform BODY VERIFICATION TEST - VER 1.

→ Replace the Axle Lock Switch in accordance with the Service

Information.
Perform BODY VERIFICATION TEST - VER 1.

151

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*AXLE LOCK INDICATOR PROBLEMS —

Continued

Symptom:

*BRAKE WARNING INDICATOR ALWAYS ON

POSSIBLE CAUSES

BRAKE WARNING INDICATOR CIRCUIT SHORT TO GROUND

BRAKE WARNING INDICATOR SWITCH

PARK BRAKE SWITCH

TEST

ACTION

APPLICABILITY

NOTE: Ensure that the Base brake system functions properly and that the
Brake Master Cylinder is filled with proper amount of fluid.
NOTE: If equipped, diagnose and repair any ABS DTCs before continuing
with this test.
Turn the ignition off.
Disconnect the Park Brake Switch harness connector.
Turn the ignition on and observe the Brake Warning Indicator.
Does the Brake Warning Indicator remain illuminated?

All

Yes

→ Go To 2

→ Replace the Park Brake Switch in accordance with the Service

Information.
Perform BODY VERIFICATION TEST - VER 1.

Turn the ignition off.
Disconnect the Brake Warning Indicator Switch harness connector.
Connect a jumper wire between cavity 1 and cavity 2.
Turn the ignition on and observe the Brake Warning Indicator.
Does the Brake Warning Indicator remain illuminated?

All

Yes

→ Repair the Brake Warning Indicator circuit for a short to ground.

Perform BODY VERIFICATION TEST - VER 1.

→ Replace the Brake Warning Indicator Switch in accordance with

the Service Information.
Perform BODY VERIFICATION TEST - VER 1.

152

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Content .. 36 37 38 39 ..