Jeep Grand Cherokee WJ. Manual - part 602

TEST

ACTION

APPLICABILITY

If there are no potential causes remaining, view repair.

All

Repair

Replace the Controller Anti-Lock Brake in accordance with the
Service Information.
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)

PUMP MOTOR CIRCUIT NOT WORKING PROPERLY —

Continued

Symptom:

RIGHT FRONT SENSOR CIRCUIT FAILURE

When Monitored and Set Condition:

RIGHT FRONT 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 FRONT WHEEL SPEED SENSOR OR CONNECTOR DAMAGE

RIGHT FRONT WHEEL SPEED SENSOR CIRCUITS SHORTED OR OPEN

CAB-NO OUTPUT

RIGHT FRONT WHEEL SPEED SENSOR -- NO OUTPUT

CAB - UNABLE TO READ RIGHT FRONT WHEEL SPEED SENSOR SIGNAL

INTERMITTENT CIRCUIT DTC

TEST

ACTION

APPLICABILITY

Turn the ignition on.
With the DRBIII

t, record and erase DTC’s.

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

t, read DTC’s.

Does the DRBIII

t display Right Front Wheel Speed Sensor Circuit Failure DTC

present right now?

All

Yes

→

Go To

→

Go To

Turn the ignition off.
Inspect the Right Front 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 Front 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 Front 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 Front 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 Left Front Wheel Speed Sensor connector.
Turn ignition on.
Measure the voltage across the Right Front Wheel Speed Sensor 12 Volt Supply and
Signal circuits at the Right Front 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 front 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 CAB.
Perform ABS VERIFICATION TEST - VER 1.

→

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

All

Yes

→

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

→

Test Complete.

BRAKES (CAB)

RIGHT FRONT SENSOR CIRCUIT FAILURE —

Continued

Symptom:

RIGHT FRONT SENSOR SIGNAL FAILURE

When Monitored and Set Condition:

RIGHT FRONT SENSOR SIGNAL FAILURE

When Monitored:

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

(ms). Wheel speed 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 FRONT WHEEL SPEED SENSOR OR CONNECTOR DAMAGED

TONE WHEEL DAMAGED

RIGHT FRONT WHEEL SPEED SENSOR AIR GAP OUT OF SPECIFICATION

WHEEL BEARINGS OUT OF SPECIFICATION

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 Front WSS Signal 0 km/h (0 mph) or differing from others by more than 5
km/h (3 mph)?

All

Yes

→

Go To

→

Go To

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

All

Yes

→

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

→

Go To

Turn the ignition off.
Inspect the Tone Wheel for damaged or missing teeth, cracks, or looseness.
Note: The Tone Wheel Teeth should be perfectly square, not bent or nicked.
Is the Tone Wheel OK?

All

Yes

→

Go To

→

Replace the Tone Wheel.
Perform ABS VERIFICATION TEST - VER 1.

BRAKES (CAB)

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