Jeep Grand Cherokee WJ. Manual - part 603

TEST

ACTION

APPLICABILITY

Turn the ignition off.
Using a Feeler Gauge, measure the Wheel Speed Sensor Air Gap.
NOTE: The Air Gap should be checked in at least four places on the Tone
Wheel.
Is the Air Gap between 0.42 mm - 1.71 mm (0.017

9 - 0.0689) ?

All

Yes

→

Go To

→

Repair as necessary.
Perform ABS VERIFICATION TEST - VER 1.

Turn the ignition off.
Inspect the wheel bearings at the affected wheel for excessive runout or clearance.
Note: Refer to the appropriate service information, if necessary, for proce-
dures or specifications.
Is the bearing clearance OK ?

All

Yes

→

Test Complete.

→

Repair as necessary.
Perform ABS VERIFICATION TEST - VER 1.

Turn the ignition off.
Visually inspect wheel speed sensor.
Visually inspect tone wheel.
Visually inspect wiring harness.
Visually inspect brakes for locking up due to lining contamination or overheating.
Inspect all Components for defects which may cause a Signal DTC to set.
Is any Component Damaged?

All

Yes

→

Repair as necessary.
Perform ABS VERIFICATION TEST - VER 1.

→

Test Complete.

BRAKES (CAB)

RIGHT FRONT SENSOR SIGNAL FAILURE —

Continued

Symptom:

RIGHT REAR SENSOR CIRCUIT FAILURE

When Monitored and Set Condition:

RIGHT REAR SENSOR CIRCUIT FAILURE

When Monitored:

Ignition on. The CAB monitors the wheel speed circuit every 7

milliseconds (ms).

Set Condition:

If the CAB detects an open or shorted wheel speed sensor circuit, the

Diagnostic Trouble Code (DTC) will set.

POSSIBLE CAUSES

RIGHT REAR WHEEL SPEED SENSOR OR CONNECTOR DAMAGE

RIGHT REAR WHEEL SPEED SENSOR CIRCUITS SHORTED OR OPEN

CAB-NO OUTPUT

RIGHT REAR WHEEL SPEED SENSOR -- NO OUTPUT

CAB - UNABLE TO READ RIGHT REAR WHEEL SPEED SENSOR SIGNAL

INTERMITTENT CIRCUIT DTC

TEST

ACTION

APPLICABILITY

Turn the ignition on.
With the DRBIII

t, read DTC’s.

With the DRBIII

t, erase DTC’s.

Turn the ignition off.
Turn the ignition on.
With the DRBIII

t, read DTC’s.

Does the DRBIII

t display Right Rear Wheel Speed Sensor Circuit Failure DTC

present right now?

All

Yes

→

Go To

→

Go To

Turn the ignition off.
Inspect the Right Rear Wheel Speed Sensor and Connector.
Is the Sensor or Connector Damaged?

All

Yes

→

Repair as necessary.
Perform ABS VERIFICATION TEST - VER 1.

→

Go To

BRAKES (CAB)

TEST

ACTION

APPLICABILITY

Turn the ignition off.
Disconnect the Right Rear Wheel Speed Sensor connector.
Note: Check connector - Clean/repair as necessary.
Disconnect the CAB connector.
Note: Check connector - Clean/repair as necessary.
Turn the ignition on.
Check the Right Rear Wheel Speed Sensor 12 volt Supply and Signal circuits for a
short to battery, ground, to each other and for open.
For the purposes of this test, a short to ground must be below 15k ohms.
Was any circuit short or open found?

All

Yes

→

Repair Right Rear Wheel Speed Sensor circuit short or open.
Perform ABS VERIFICATION TEST - VER 1.

→

Go To

Turn ignition off.
Make sure the CAB is not disconnected.
Disconnect the Right Rear Wheel Speed Sensor connector.
Turn ignition on.
Measure the voltage across the Right Rear Wheel Speed Sensor 12 Volt Supply and
Signal circuits at the Right Rear Wheel Speed Sensor connector.
Is the voltage above 10 volts?

All

Yes

→

Go To

→

Replace the Controller Antilock Brake in accordance with the
Service Information.
Perform ABS VERIFICATION TEST - VER 1.

Turn ignition off.
Disconnect the CAB harness connector.
Remove the harness strain relief to access the wires in the CAB connector.
Using a DC voltmeter and special tool 6801, backprobe the Wheel Speed Sensor 12
volt Supply and Signal circuits at the CAB.
Reconnect the CAB.
Turn ignition on.
Slowly rotate the right rear wheel while observing voltmeter reading.
Does the voltage change from approximately 1.6 volts to 0.8 volts as the wheel is
rotated?

All

Yes

→

Replace the Controller Anti-Lock Brake in accordance with the
Service Information.
Perform ABS VERIFICATION TEST - VER 1.

→

Replace the Right Rear Wheel Speed Sensor.
Perform ABS VERIFICATION TEST - VER 1.

Turn the ignition off.
Visually inspect the related wiring harness. Look for any chafed, pierced, pinched, or
partially broken wires.
Visually inspect the related wire harness connectors. Look for broken, bent, pushed
out, or corroded terminals.
Refer to any Hotline letters or Technical Service Bulletins that may apply.
Were any problems found?

All

Yes

→

Repair as necessary.
Perform ABS VERIFICATION TEST - VER 1.

→

Test Complete.

BRAKES (CAB)

RIGHT REAR SENSOR CIRCUIT FAILURE —

Continued

Symptom:

RIGHT REAR SENSOR SIGNAL FAILURE

When Monitored and Set Condition:

RIGHT REAR SENSOR SIGNAL FAILURE

When Monitored:

Wheel speed comparison is checked at drive off or every 7 milliseconds

(ms). Wheel speed circuit continuity is checked every 7 milliseconds. Wheel speed phase
length supervision is checked every 7 milliseconds.

Set Condition:

If, during an ABS stop, the CAB commands any valve solenoid on for an

extended length of time, and does not see a corresponding wheel speed change, the
Diagnostic Trouble Code (DTC) is set. The DTC can also set if the signal is missing or
erratic.

POSSIBLE CAUSES

RIGHT REAR WHEEL SPEED SENSOR OR CONNECTOR DAMAGED

TONE WHEEL DAMAGED

RIGHT REAR WHEEL SPEED SENSOR AIR GAP OUT OF SPECIFICATION

WHEEL BEARINGS OUT OF SPECIFICATION

RIGHT REAR WHEEL SPEED SENSOR INOPERATIVE

CAB - WON’T RESPOND TO WHEEL SPEED SENSOR SIGNAL

INTERMITTENT SIGNAL DTC

TEST

ACTION

APPLICABILITY

Turn the ignition on.
While an assistant drives, use the DRBIII

t to monitor all Wheel Speed Sensors.

Slowly accelerate as straight as possible from a stop to 24 Km/h (15 Mph).
With the DRBIII

t, monitor all wheel speed sensors.

Is Right Rear WSS Signal 0 Km/h (0 Mph) or differing from others by more than
5kmh (3mph)?

All

Yes

→

Go To

→

Go To

Turn the ignition off.
Inspect the Right Rear Wheel Speed Sensor and Connector.
Is the Sensor or Connector damaged?

All

Yes

→

Repair as necessary.
Perform ABS VERIFICATION TEST - VER 1.

→

Go To

BRAKES (CAB)

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