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Discussion Starter #1
car was driving then stalled out , wouldnt start after had it towed home ,
getting code p0340 changed the crankshaft position sensor 3 times thinking bad sensor,... then i tested the plug for the crankshaft sensor. i have ground and 0.5v to yellow but the middle i dont have 12v with key on or cranking ..
what other pins should i be checking on the pcm or thinking ignition wire might be an issue? anything i can jump to test
 

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P0340 is for the camshaft position sensor. P0335 is for the crankshaft position sensor.
Either way, the connector to the sensors look the same (3-wire plug). You should not see 12V. The PCM supplies the sensors with 5V. The sensors then return a signal back to the PCM.
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Pin on the right is the 5V supply. Pin on the left is the signal circuit. Pin in the middle is the ground circuit.
To test the 5V supply and signal circuits ...
Turn the ignition off.
Disconnect the CMP Sensor harness connector.
Ignition on, engine not running.
Measure the voltage on the 5-volt Supply circuit in the CMP Sensor harness connector. Voltage should be in the range of 4.5V - 5.2V
Measure the voltage on the CMP Signal circuit in the CMP Sensor harness connector. Voltage should be in the range of 4.5V - 5V
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Discussion Starter #3
you are right camshaft , yellow is 5v ,middle wire i get 0 volts and not ground right side i get ground blue wire i believe ..with key on
 

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They may have changed the pin assignments from one model year to another.
Yellow/pink is 5V supply. Dark blue/dark green is ground and dark blue/gray is the sensor return signal.
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Discussion Starter #5
should i be able to see 5 volt suppy with key on ? i dont see anything when cranking ..i do have ground and 5 volt to yellow pink..since i dont see 5volt supply its probably a bad pcm then? what wire is it on the pcm connector
 

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Discussion Starter #6
i will have to check in the morning for the colors from what i think i have is 5 volt on yellow nothing for middle wire , end wire is ground just have to check the colors
 

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When testing the connector for voltage ...
Turn the ignition off.
Disconnect the CMP Sensor harness connector.
Ignition on, engine not running.
Check the pins for voltage.
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Using the OEM Mopar sensors is best. Some of the aftermarket brands don't perform as well. If you're getting 0.5V on the 5V supply circuit the sensor is not going to function; therefore you will not get a voltage output on the return signal. Either the PCM is not supplying 5V to the sensor or the wiring harness/connectors on the 5V supply to the camshaft position sensor is bad.

If you're getting 5V supply to other sensors (e.g. crankshaft position sensor) then it's not the 5V supply in the PCM. Instead it's the delivery of 5V between the PCM and the camshaft position sensor. Check the wiring harness/connectors between the camshaft position sensor and the PCM. Look for cracking/fraying, splits, corrosion, etc...

You can unplug the PCM connector to check the condition of the pins/connector but don't probe the PCM harness connector. Probing the PCM harness connectors can damage the PCM terminals. There's an adapter tool that's plugged onto the PCM harness connector for probing without damage to the PCM.

Without the adapter tool you will not be able to perform any resistance checks but you can perform a voltage check to see if the the 5V supply circuit is shorted to battery voltage.

Turn the ignition off.
Disconnect the PCM harness connectors.
Ignition on, engine not running.
Measure the voltage on the 5-volt Supply circuit in the camshaft sensor harness connector.
If the voltage is above 0V, there's a short to battery voltage in the 5-volt supply circuit.
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Discussion Starter #11
i changed the pcm today and re checked the wiring to camshaft sensor , with it unpluged yellow wire .5 volts middle wire i now see .5 volts and end is ground , with harness pluged into sensor yellow wire is .5 volts middle wire is .01 volts end is ground ..still no start and still have p0340
 

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There seems to be a definite problem in getting the 5V supply to the sensor. The manifold absolute pressure (MAP) sensor is on the same power and ground circuit as the camshaft sensor. You may want to check the MAP connections to see if they are interfering with the camshaft sensor.

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Discussion Starter #14
wouldnt i have a code for map sensor if that was an issue to..car has been down for 3 weeks now would like to get it running
 

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You would think a MAP sensor code would get logged but it may be getting the 5V supply.
In engine startup mode the PCM receives inputs from:
² Battery voltage
² Engine coolant temperature sensor
² Crankshaft position sensor
² Intake manifold air temperature sensor
² Manifold absolute pressure (MAP) sensor
² Throttle position sensor (TPS)
² Starter motor relay
² Camshaft position sensor signal
The PCM monitors the crankshaft position sensor. If the PCM does not receive a crankshaft position sensor signal within approximately 3 seconds of cranking the engine, it will shut down the fuel injection system.

If there's a problem with these sensors, or they're unplugged, the engine will not start/run. A good battery is required. Load test the battery to make sure there's no issues with the battery. Sometimes the P0340 code gets set because of the crankshaft position sensor ... it's not common but it's not impossible. You can unplug the MAP sensor or crankshaft sensor and test them for 5V supply the same way you check the camshaft sensor (3-pin connector) with 5V, return signal and ground. The PCM is the 5V source for all three of these sensors.
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Crankshaft position sensor is on the passenger side. Short video shows it with the engine removed.

I'm not aware of any jumper fixes for the sensors The PCM is expecting active signals from these sensors and bypassing the sensors is the same as removing the sensors. The PCM will not see an active signal and will not allow the engine to start/run. Without the crankshaft/camshaft signals the PCM does not know where to set fuel injection, spark advance, etc...
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Discussion Starter #19 (Edited)
ok ened up changeing the crank shaft sensor ,also changed the maf sensor ,have 5 volts on all 3 sensors on 2 wires each and all 3 have ground ...still no start i dont even know where else to look , tried with both pcms also same thing
not sure why i was saying .5 volts i meant 5 volts
 

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Sounds like the PCM is delivering the 5V supply and all three sensors are able to return 5V signal. Have you cleared the codes and looked to see if any new codes are being logged?

During engine start-up mode ...
If the PCM receives the camshaft position sensor and crankshaft position sensor signals, it energizes the Auto Shutdown (ASD) relay and fuel pump relay. The ASD and fuel pump relays supply battery voltage to the fuel pump, fuel injectors, ignition coil, (EGR solenoid and PCV heater if equipped) and heated oxygen sensors.

Check the ASD and fuel pump relays and fuses to make sure they're working. ASD relay and fuses are in the front fuse box (engine compartment). The fuel pump relay and fuses are in the rear fuse box (trunk).
Check all the engine and chassis ground wire connections to make sure there's good grounding. If the starter is turning the engine the problem is not the starter, starter relay, run-start relay, etc ... It's something with the ignition or fuel systems.

The 3.5L has a timing belt. How many miles on the engine and has the timing belt ever been changed?
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