Jeep Grand Cherokee WK. Manual — part 157

C121C-TORQUE REQUEST SIGNAL DENIED (CONTINUED)

3.

CHECK THE (D65) CAN C (+) BUS AND (D64) CAN C (-) BUS CIRCUITS FOR A SHORT TOGETHER

Turn the ignition off.

Disconnect the Anti-Lock Brake Module harness connector.

Measure the resistance between the (D65) CAN C (+) BUS circuit and
the (D64) CAN C (-) BUS circuit.

Is the resistance below 150 ohms?

Yes

>> Repair the (D65) CAN C (+) BUS and the (D64) CAN C (-)

BUS circuits for a short together.

Perform ABS VERIFICATION TEST - VER 1.

No

>> Go To 4

4.

CHECK THE (D65) CAN C (+) BUS CIRCUIT FOR A SHORT TO GROUND

Turn the ignition off.

Disconnect the Powertrain Control Module harness connector.

Measure the resistance between ground and the (D65) CAN C (+)
BUS circuit.

Is the resistance below 5.0 ohms?

Yes

>> Repair the (D65) CAN C (+) BUS circuit for a short to

ground.

Perform ABS VERIFICATION TEST - VER 1.

No

>> Go To 5

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BRAKES - BRAKE CONTROLLER ELECTRICAL DIAGNOSTICS

WK

C121C-TORQUE REQUEST SIGNAL DENIED (CONTINUED)

5.

CHECK THE (D65) CAN C (+) BUS CIRCUIT FOR A SHORT TO VOLTAGE

Turn the ignition on.

Measure the voltage of the (D65) CAN C (+) BUS circuit.

Is there any voltage present?

Yes

>> Repair the (D65) CAN C (+) BUS circuit for a short to volt-

age.

Perform ABS VERIFICATION TEST - VER 1.

No

>> Go To 6

6.

CHECK THE (D65) CAN C (+) BUS CIRCUIT FOR AN OPEN CIRCUIT

Turn the ignition off.

Measure the resistance of the (D65) CAN C (+) Bus circuit.

Is the resistance below 5.0 ohms?

Yes

>> Go To 7

No

>> Repair the (D65) CAN C (+) BUS circuit for an open cir-

cuit.

Perform ABS VERIFICATION TEST - VER 1.

WK

BRAKES - BRAKE CONTROLLER ELECTRICAL DIAGNOSTICS

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C121C-TORQUE REQUEST SIGNAL DENIED (CONTINUED)

7.

CHECK THE (D64) CAN C (-) BUS CIRCUIT FOR A SHORT TO GROUND

Turn the ignition off.

Measure the resistance between ground and the (D64) CAN C (-) BUS
circuit.

Is the resistance below 5.0 ohms?

Yes

>> Repair the (D64) CAN C (-) BUS circuit for a short to

ground.

Perform ABS VERIFICATION TEST - VER 1.

No

>> Go To 8

8.

CHECK THE (D64) CAN C (-) BUS CIRCUIT FOR A SHORT TO VOLTAGE

Turn the ignition on.

Measure the voltage of the (D64) CAN C (+) BUS circuit.

Is there any voltage present?

Yes

>> Repair the (D64) CAN C (-) BUS circuit for a short to volt-

age.

Perform ABS VERIFICATION TEST - VER 1.

No

>> Go To 9

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BRAKES - BRAKE CONTROLLER ELECTRICAL DIAGNOSTICS

WK

C121C-TORQUE REQUEST SIGNAL DENIED (CONTINUED)

9.

CHECK THE (D64) CAN C (-) BUS CIRCUIT FOR AN OPEN CIRCUIT

Turn the ignition off.

Measure the resistance of the (D64) CAN C (-) Bus circuit.

Is the resistance below 5.0 ohms?

Yes

>> Replace the Powertrain Control Module in accordance with

the Service Information.

Perform ABS VERIFICATION TEST - VER 1.

No

>> Repair the (D64) CAN C (-) BUS circuit for an open circuit.

Perform ABS VERIFICATION TEST - VER 1.

WK

BRAKES - BRAKE CONTROLLER ELECTRICAL DIAGNOSTICS

5 - 257