B@W (Bored at Work) 2023

[sonicsdaman]

new year new thread!

Fiat 500 P0339-00-CRANKSHAFT POSITION SENSOR INTERMITTENT


The PCM uses each CKP signal pulse to determine crankshaft speed and decodes the crankshaft tone wheel reference gap to identify crankshaft position.
This information is then used to sequence the ignition timing and fuel injection events for the engine. The PCM also uses CKP Sensor output information to determine the crankshaft relative position to the camshaft, to detect cylinder misfire and to control the CMP actuator if equipped.




WHEN MONITORED
While cranking the engine and with the engine running.


SET CONDITION
When the CKP Sensor failure counter reaches 20. One Trip Fault. Three good trips to turn off the MIL.


POSSIBLE CAUSES
Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding.




DIAGNOSTIC TEST
1. CHECK FOR APPLICABLE TSB
1. Check for any applicable TSBs that may apply for this issue.


Were any TSBs applicable?
Yes
Perform the applicable TSB. Erase the DTC and perform the verification test.


No


Possible Causes
5-VOLT SUPPLY CIRCUIT SHORTED TO VOLTAGE
5-VOLT SUPPLY CIRCUIT SHORTED TO GROUND
5-VOLT SUPPLY CIRCUIT SHORTED TO THE CKP SENSOR GROUND CIRCUIT
5-VOLT SUPPLY CIRCUIT OPEN/HIGH RESISTANCE
CKP SIGNAL CIRCUIT SHORTED TO VOLTAGE
CKP SIGNAL CIRCUIT SHORTED TO GROUND
CKP SIGNAL CIRCUIT SHORTED TO THE CKP SENSOR GROUND CIRCUIT
CKP SIGNAL CIRCUIT OPEN/HIGH RESISTANCE
CKP SENSOR GROUND CIRCUIT OPEN/HIGH RESISTANCE
CRANKSHAFT POSITION SENSOR
POWERTRAIN CONTROL MODULE (PCM)

thank you

Yep, crankshaft position sensor. Sometimes it's a damaged wire or a corroded connector. If you replace the sensor it sometimes might need to be "realigned"... resynched using computer software. There are also vids on how to test the sensors.

oh great might have to remove the exhaust

[Fiat500USA]

Happy New Year y'all Here's hoping for smooth sailings for everyone.

[Fiat500USA]

new year new thread!

thank you

oh great might have to remove the exhaust

Thanks, you beat me too it! Sorry you're having an issue. If you haven't driven the car that much, maybe the connection or wire deteriorated.

Ha, I just read what MAP wrote and it's like the same thing! I need to pay more attention!

Good luck!

[sonicsdaman]

It's odd the way it happened. Drove it the night before no issues, parked it. went to go out on new years day and it hesitated to start then acted like an ignition or fueling problem. Rough idle, stalled, couldn't rev past 3k, no blinking CEL tho.

Being the dorito owner that I am I initially thought I blew it up, timing belt slipped or something.

I did get it started and made a quick drive from the front of the house to the back so it's not in the way at least.



How's everyone elses new year going?


oh and did I mention that during the negative degree weather we had a few weeks ago that my subarus drivers doors latch got frozen and didn't latch the door closed. That first right hand turn really came as a surprise

[sonicsdaman]

Welp got home started poking around the engine bay and snapped the hard plastic vacuum line. Part# 4627485AC
🙃

[Fiat500USA]

Welp got home started poking around the engine bay and snapped the hard plastic vacuum line. Part# 4627485AC


That sux! Every time I touch mine, I'm wondering when it will break.

[sonicsdaman]

all, got the vacuum line all fixed up. But I for the love of me can't find the crankshaft position sensor. Anyone have a diagram/location pic they can share?

[map]

The tech shows the location (vid in #1). IIRC it's easiest after removing the battery but can be reached w/o. (I haven't pulled mine.)

[Fiat500USA]

Sorry for the delay getting to you.

The Crankshaft Position (CKP) sensor is mounted into the left side of the cylinder block at the front of the
engine. It is positioned to read the tonewheel mounted on the vibration damper.



From this post with pictures:

Thank you for the additional info.


Besides the CPS, and the absence of the oil temp sender, the harnesses and other sensors/connectors are all the same.


I swapped the harness over today, and installed the front crank sensor, separated out the oil temp sender harness so I can use the sensor as the drain plug. No provision for the sensor in the pan, or a spot I can drill & tap. Not swapping the pan, that's a PITA.










Did the selector shaft seal, swapped over the flywheel & clutch, re-attached the trans & got it all ready to go back in the car tomorrow

Another image you can just see it:

[Fiat500USA]

Another post with video:

Teknical1; sorry to hear of your issue.

I found this video on YouTube and I read it depends whether you have a manual or automatic for the location.

Jump to the 22:10 mark for discussion about the location

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