Jeep Liberty KJ. Manual — part 617

13.

MAP SENSOR

Turn the ignition off.

Connect the C1 PCM harness connector.

Ignition on, engine not running.

With a scan tool, monitor the MAP Sensor voltage.

Connect a jumper wire between the (K1) MAP Signal circuit and the
(K900) Sensor ground circuit.

Does the scan tool display MAP voltage from approximately 4.9
volts to below 0.5 of a volt with the jumper wire installed?

Yes

>> Replace the MAP Sensor.

Perform the POWERTRAIN VERIFICATION TEST. (Refer to
9 - ENGINE - STANDARD PROCEDURE)

No

>> Go To 14

NOTE: Remove the jumper wire before continuing.

14.

EXCESSIVE RESISTANCE IN THE (K1) MAP SIGNAL CIRCUIT

Turn the ignition off.

Disconnect the C2 PCM harness connector.

CAUTION: Do not probe the PCM harness connectors. Probing the
PCM harness connectors will damage the PCM terminals resulting
in poor terminal to pin connection. Install Miller Special Tool #8815
to perform diagnosis.
Measure the resistance of the (K1) MAP Signal circuit from the MAP
Sensor harness connector to the appropriate terminal of special tool
#8815.

Is the resistance below 5.0 ohms?

Yes

>> Go To 15

No

>> Repair the excessive resistance in the (K1) MAP Signal cir-

cuit

Perform the POWERTRAIN VERIFICATION TEST. (Refer to
9 - ENGINE - STANDARD PROCEDURE)

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ENGINE ELECTRICAL DIAGNOSTICS

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15.

(K1) MAP SIGNAL CIRCUIT SHORTED TO GROUND

Measure the resistance between ground and the (K1) MAP Signal cir-
cuit in the MAP Sensor harness connector.

Is the resistance below 100 ohms?

Yes

>> Repair the short to ground in the (K1) MAP Signal circuit.

Perform the POWERTRAIN VERIFICATION TEST. (Refer to
9 - ENGINE - STANDARD PROCEDURE)

No

>>

Go To 16

16.

EXCESSIVE RESISTANCE IN THE (K900) SENSOR GROUND CIRCUIT

CAUTION: Do not probe the PCM harness connectors. Probing the
PCM harness connectors will damage the PCM terminals resulting
in poor terminal to pin connection. Install Miller Special Tool #8815
to perform diagnosis.
Measure the resistance of the (K900) Sensor ground circuit from the
MAP Sensor harness connector to the appropriate terminal of special
tool #8815.

Is the resistance below 5.0 ohms?

Yes

>> Go To 17

No

>> Repair the excessive resistance in the (K900) Sensor

ground circuit.

Perform the POWERTRAIN VERIFICATION TEST. (Refer to
9 - ENGINE - STANDARD PROCEDURE)

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ENGINE ELECTRICAL DIAGNOSTICS

9 - 527

17.

PCM

NOTE: Before continuing, check the PCM harness connector terminals for corrosion, damage, or terminal
push out. Repair as necessary.
Using the schematics as a guide, inspect the wire harness and connectors. Pay particular attention to all Power and
Ground circuits.

Were there any problems found?

Yes

>> Repair as necessary.

Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)

No

>> Replace and program the Powertrain Control Module per Service Information.

Perform the POWERTRAIN VERIFICATION TEST. (Refer to 9 - ENGINE - STANDARD PROCEDURE)

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ENGINE ELECTRICAL DIAGNOSTICS

KJ

P2096-DOWNSTREAM FUEL TRIM SYSTEM 1 LEAN

For a complete wiring diagram Refer to Section 8W.

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ENGINE ELECTRICAL DIAGNOSTICS

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