Mechanics

JEEP GRAND CHEROKEE SENSOR PROBLEM

1999 Jeep Grand Cherokee • 190,213 miles

I have a 1999 Jeep Grand Cherokee 4.7L V8 and it is showing error code P0340 Camshaft Position Sensor Bank A - Circuit Malfunction. I have replaced the Camshaft Position Sensor And Crankshaft Position Sensor with Mopar Parts. Im still receiving the same error code and I can not get my Jeep to start to even attempt to take it to a mechanic to figure out what exactly is wrong. I was told to check the Continuity of the circuit and the sensor but I have no clue how. I have a OHM Meter but again I am clueless to what exactly I need to do. Please Help!
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Schmash
October 27, 2012.




Test orange wire for 5 volts, if volts less than 4.5 repair open in circuit.

3. Turn ignition off. Ensure CMP sensor connector is still disconnected. Using an ohmmeter,  check resistance between CMP sensor connector,  5 volt supply circuit (Orange wire) and signal circuit (Tan/Yellow wire).
If resistance is 5 ohms or more,  go to next step. If resistance is less than 5 ohms,  repair 5 volt supply circuit for short to signal circuit. Perform TEST VER 5A.
4. Ensure ignition is off. Ensure CMP sensor connector is still disconnected. Turn ignition on,  with engine off. Using a voltmeter,  check voltage on CMP sensor connector,  signal circuit (Tan/Yellow wire). If voltage is
less than 4.5 volts,  go to next step. If voltage is 4.5 5.5 volts,  go to step 9). If voltage is more than 5.5 volts,  repair signal circuit for short to voltage. Perform TEST VER 5A.
5. Turn ignition off. Ensure CMP sensor connector is still disconnected. Disconnect PCM connectors. PCM is located in engine compartment. See PCM LOCATION table under SYSTEM DIAGNOSTICS. Clean
and/or repair connectors as necessary. Using an ohmmeter,  check resistance of CMP sensor signal circuit (Tan/Yellow wire) between CMP sensor connector and PCM. If resistance is less than 5 ohms,  go to next
step. If resistance is 5 ohms or more,  repair open signal circuit. Perform TEST VER 5A.
6. Turn ignition off. Ensure CMP sensor and PCM connectors are still disconnected. Using ohmmeter,  check resistance between ground and CMP sensor connector,  signal circuit (Tan/Yellow wire). If resistance is 5
ohms or more,  go to next step. If resistance is less than 5 ohms,  repair signal circuit for short to ground. Perform TEST VER 5A.
7. Ensure ignition is off. Ensure CMP sensor and PCM connectors are still disconnected. Using ohmmeter,  check resistance between CMP sensor connector,  signal circuit (Tan/Yellow wire) and sensor ground
circuit (Black/Light Blue wire). If resistance is 5 ohms or more,  go to next step. If resistance is less than 5 ohms,  repair signal circuit for short to sensor ground circuit. Perform TEST VER 5A.
8. At this time,  PCM is assumed to be defective. Replace PCM. Perform TEST VER 5A.
9. Ensure ignition is off. Ensure CMP sensor connector is still disconnected. Using an ohmmeter,  check resistance between ground and CMP sensor connector,  sensor ground circuit (Black/Light Blue wire). If
resistance is less than 5 ohms,  go to next step. If resistance is 5 ohms or more,  go to step 12).
10. Ensure ignition is off. Ensure CMP sensor connector is still disconnected. Remove CMP sensor. See Fig. 28 or Fig. 29 . Inspect tone wheel/flexplate for physical damage. Ensure tone wheel/flexplate rotates when
engine is cranked. If tone wheel/flexplate is okay,  go to next step. If tone wheel/flexplate is damaged,  repair or replace as necessary.
11. At this time,  CMP sensor is assumed to be defective. Replace CMP sensor. Perform TEST VER 5A.
12. Turn ignition off. Ensure CMP sensor connector is still disconnected. Disconnect PCM connectors. PCM is located in engine compartment. See PCM LOCATION table under SYSTEM DIAGNOSTICS. Clean
and/or repair connectors as necessary. Using an ohmmeter,  check resistance of CMP sensor ground circuit (Black/Light Blue wire) between CMP sensor connector and PCM. If resistance is less than 5 ohms,  go
to next step. If resistance is 5 ohms or more,  repair open sensor ground circuit. Perform TEST VER 5A.
13. At this time,  PCM is assumed to be defective. Replace PCM. Perform TEST VER 5A.
Test ver 5a is using a labscope so if you can't get it rnning by this time tow to a repair shop it still may not be your pcm. Also check for blown fusesin power dist box and check fuse 19 and 6 as well as automatic shutdown relay as that may be the problem as well.
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Hmac300
Oct 27, 2012.
Schm, ash, also make sure the connectors are clean and firmly seated on the sensors. Make sure the sensors are properly gapped. Using the Ohm meter, clip the leads to the sensor and crank the engine, while watching the meter. Does resistance go to zero?

Rivermikerat
Oct 31, 2012.

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