Had these codes, replaced the CPS, cleared the codes, and still have codes. Returning PCM to Stock (SCT) and if that doesnt work I will reset pcm.. Any suggestions ? thanks.

 

found answer on another site, a/c line wore away wiring:
http://www.ford-trucks.com/forums/10...and-p0349.html

 

Taped up one wire that was shorting onto a/c line. closed up the loom, still have the codes after clearing them.

 

Bueller, Bueller, ...

 

Is it possible the shorted wire could have damaged the sensor?

 

nu-supercrew; ;


Couple of things to keep in mind. P0340 code is checked / set very early in each run cycle, ie: Starting (http://www.autocodes.com/p0340_ford.html). Thus, a weak battery OR heaver than normal starter current can cause a voltage drop harmful to the 'sensitive' sensor (CKP) effectiveness. Also (further evidence of the sensitivity of this particular sensor), the wiring diagram (http://www.devoll.com/Public/f150-5_...nce-wiring.pdf ) at the top right of page 2 indicates that the CKP sensor wiring is shielded / grounded at G103, [R/R of Engine Compartment]. If your chaffing got through the insulation, it probably would only have exposed the 'shield'. Shorting the 'shield' alone would have induced additional noise, but would NOT have been destructive to or damaged your new sensor. However, if the chaffing got through the shield and effected EITHER conductor - they both go straight to the PCM - as indicated by the wiring diagram. THAT could have damaged the PCM !!!!!!


I have also read on these forums that a One bad diode out of the four in the Alternator can keep the battery charged but cause noise on the electrical circuits resulting in a P0340. The cam position sensor wheel just has one 'missing' tooth that the 'sensor' detects to determine TDC. Noise on the circuit can confuse it easily. Just make sure your grounds, battery, starter, alternator and electrical systems are clean.


Good luck

 

Thank you very much for the information. I will heed your advice and post findings. Cheers!

 

Cam position sensor is at top of page 3. You called out the location of the CRANK position sensor.

 

The wire that was worn and bare against the A/C line is position # 43 BLK/WHT and is labeled CMCV MON. any idea what CMCV means? charge motion control valve??? The next pin, #44 is CMP SENS 2, could the neighboring wire grounding out on the a/c line cause a problem here?

 

Checked the 2 old sensors ohm resistance, both good. Checked the new ones, also good. Disconnected alternator, performed diode check, good. Am I at the stage where I replace the PCM? I suppose the grounded out #43 blk/wht wire could have caused a problem in the pcm?

 

https://www.f150online.com/forums/v8-engines/507851-p0340-p0345.html

 

You are correct, my apologies please. In the other post I was immediately thinking (from memory - assumed) one code was Crank - and one was Cam sensor. Guess I would also say that I wouldn't have thought the Cam Position Sensor wiring would chaff against the A/C lines !?!?!?.


I think your assessment is correct that the designation CMCV MON (@ #43) on the wiring diagram would be "Charge Motion Control Monitor" wire. If the wire you found chaffed was black/white, I would tend to agree based on the schematic. Seems like Cam Position sensor wires (which are NOT shielded like I mentioned in my prior post), are DK-GRN & ORG on the sensor side.


On further review of the wiring diagram, I do note with interest that the 'common' wire to the Cam Position Sensors (GRY-RED) are also common to a BUNCH OF STUFF terminated at Pin #58 designated as "SIGNAL RETURN". This seems to include stuff like Cylinder Head Temp, MAF sensor, EOT sensor, Fuel Rail Pressure Temperature, etc-etc. (That's scary !) Since your codes point to BOTH cam position sensors, are you having any other symptoms that would point to those other sensors? Or can you ring those wires out for good continuity back to the CPS, or check output / inputs to some of those sensors. This makes me think it still might NOT be a bad PCM if you are not having problems with any of these other sensors/circuits.


Another document that I have that might help is standard reference values for many of those sensor inputs and or outputs. You can grab it here http://www.devoll.com/Public/5-4L_3v...nce_values.pdf . Hope this helps.

 

RESPONDED in your new thread concerning this issue: https://www.f150online.com/forums/v8...0-pcm-bad.html

 

F150Torqued, you're help has been tremendous! Next step, I think, is to "ring out" those CPS wires from end to end. (When you said " ring out" it reminded me of the crank operated resistance meters I used in the Navy).
As far as Other symptoms, it feels like the engine has a brake that is engaged. Sluggish. Which, given what I have found so far, makes me want to check operation of the Charge Motion Control. Although the codes don't indicate that exactly. Thank you for the schematic links and such as they have proved to be invalueable.

Regards, Nu-suprrcrew.

 

Not to butt in...as you know Tourqued, I am dealing with issues of my own with my 05...on the charts that you linked to, is KOEO key on engine on, key off engine off, key on engine off? The info seems useful in looking at the info my scanner gives me...

Keep up the good fight in trying to diagnose these gremlins!