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With that code, here's what I did:

1. Get in.
2. Turn key.
3. Drive.

It also worked for @jedwards1654 with the same code.
Because it appears that you have a "stored" code. It is an intermittent error according to the screen capture you posted.
"The Stored DTC does not set the MIL and is
erased after 40 key cycles. "

PIM problems appear to be the DC-DC converter issues. When the DC-DC converter fails, It kills the 12 volt battery. I think that if 12 volt battery sensor (IBS) is broken, PIM DC-DC converter is unable to "see" the voltage it is sending out and reports a DTC. I have a feeling that many 500e's have a broken IBS.

Remember that BPCM for the HV battery runs of the 12 volt battery. If the DC-DC converter is not working, it is unable to maintain the 12 volt system.
 

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PIM problems appear to be the DC-DC converter issues. When the DC-DC converter fails, It kills the 12 volt battery.
If that was happening, a new 12V battery would work*, but sometimes it doesn't, due to a computer glitch. In those cases it works fine if the humidity sensor is left unplugged & the codes are cleared with a $30 dongle & free phone app.

Except at a dealership where they say you have to pay them $8,500 for a new PIM (up from $6k not long ago).

* for a while, like a gas car with a dead alternator.
I think that if 12 volt battery sensor (IBS) is broken, PIM DC-DC converter is unable to "see" the voltage it is sending out and reports a DTC. I have a feeling that many 500e's have a broken IBS.
But here is the @Iceman 500e, working fine with NO 12 volt battery sensor at all:
Motor vehicle Automotive tire Yellow Automotive design Automotive exterior
 

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You did not misunderstand. With an OEM-sized 12V battery the foam is to insulate it from the heat of the adjacent OnBoard Charger Module on the passenger side.
Electrical wiring Font Computer hardware Gas Audio equipment

@Iceman has a downsized battery like me, which allowed space for him to surround it with foam on ALL sides (except the top*) to protect his lithium-ion investment. I didn't bother, since mine is even further from the heat, & also only $35 lead-acid so I don't care so much if it dies, although it's still going strong after nearly 22 months ($1.59/month, if it dies tomorrow):
Motor vehicle Car Hood Automotive tire Automotive design

* The red part showing is the ENTIRE top of the battery! The battery is actually a bit smaller than either of the foam blocks on each side of it!
 

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$4700 +tax at Fiat in Downey, according to the OP, on page 1 of this thread. However I didn't re-read every post to make sure they tried all the tricks in case it isn't really even the PIM at all. I'm pretty sure that if the car will drive, the PIM has to be ok.
I just purchased a 500e with a bad PIM, according to the owner the Costa Mesa Fiat dealer the code was POA8D which pointed to the Power Inverter Module, the owner was being charged $8,625.00, I own exact same car for a year so I remove the PIM off my car and tried the supposedly bad one just to make sure I don't throw way money for a PIM replacement, I'm speaking to a friend who works on Boats and RV on Solar power Inverter with a charging system in one unit, maybe he can rebuild it for me, I'll update
 

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THANK YOU!

I am not the only one on this forum who will be very happy to learn that a used PIM from another car will work, although apparently that requires some sort of reprogramming. Click to enlarge:
Product Rectangle Font Parallel Slope

The prior owner likely didn't know to leave the error-causing humidity sensor unplugged:
*
Circuit component Machine Electronic engineering Hardware programmer Computer hardware

They likely also didn't know the 500e nearly never gives any warning of 12V starter battery failure**. When that happens with the sensor connected, one of the FAKE codes that can appear is P0A8D, with a zero, not an upper-case "o".

It is one of the 2 codes dealerships use as so-called "proof" that you "need" to pay them $8,625.00:
Font Material property Parallel Screenshot Document

HOWEVER, in nearly 7 years closely following this forum, & a few years on the other one, I've only read one case where PIM replacement worked. In ALL the many other cases I've read, PIM replacement made no difference, indicating it was likely fine.

As one example of that, about 8 weeks ago, after 12V failure/replacement @jedwards1654 got the same code as you, PLUS the other code on that doc above:
Font Screenshot Parallel Rectangle Technology

The car wouldn't drive OR charge but it was fine after simply clearing the codes with the free "demo" version of the AlfaOBD app & an over-priced Konnwei KW902: $30 to get it fast from Amazon, instead of $17 on eBay.

Prior to clearing, a 30-hour 12V disconnect was done, with a 5-minute HV disconnect prior to 12V reconnection:
Food Gesture Screenshot Terrestrial plant Font

Full-size pic included just in case, since it's SO easy to get wrong:
Food Gesture Screenshot Terrestrial plant Font

Those disconnects made no apparent difference, but they may have been required in order for the codes to clear later.

* Middle fingers in each opening, pull perpendicular away from glass, ROUND toothpick to wedge open the black socket, pull out purple plug, tuck inside, cover hooks on left & snaps up on right.

** So a $26 BM2 Bluetooth alarm is very good to have, available at Amazon, eBay, Walmart.com...
Product Automotive lighting Font Gadget Technology
 

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If someone could prove that installing a used PIM would fix the PIM issue, that would be a gamechanger for MANY people on these Fiat 500e forums. There are plenty of them available for $800-$900 apiece on LKQ auto salvage, but the local Fiat Dealer and Fiat USA told me repeatedly that a used PIM could not be reprogrammed with your VIN and therefor would not work. The last time I spoke with the local Fiat dealer, he said this a different way...he said that if one installs a used PIM, and if the HV battery ALSO needs to be replaced under warrantee, Fiat USA can point to the difference in VIN in the used PIM as a way to get out of paying for the HV battery replacement. This is interesting as the replacement of the PIM should solve many of these Fiat 500e issues without the need to replace the HV battery. But of course he told me this just after I had sold my 500e for $3000 to a mechanic who wants to try to fix it himself.

I hope someone does try to install a used PIM to resolve this common PIM failure. If it works, I'll buy another Fiat with PIM failure and will fix it up!

thanks, all, and especially Electric Tire Shredder, for the advice and help.
Hey Jeff, just updating on the progress with the car, here's what I found so far, I was able to get it into drive and reverse a few times after cleaning a bunch of grounds and both battery terminals .did find the positive kinda loose not at the battery post but the nut that holds two wires on there. But couldn't get the dc-dc converter to work and charge the 12v battery. Pulled the PIM , pulled the covers off to check the internal fuses (fuses good) . Smelled of fried electronics inside. Had a friend that does board repairs take a look at it and said some capacitors blew and took a chip with them, so it's not repairable.
Currently waiting for a used PIM. Hope this info is helpful to someone, will come back and update once I install the used PIM.
 

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Hey Jeff, just updating on the progress with the car, here's what I found so far, I was able to get it into drive and reverse a few times after cleaning a bunch of grounds and both battery terminals .did find the positive kinda loose not at the battery post but the nut that holds two wires on there. But couldn't get the dc-dc converter to work and charge the 12v battery. Pulled the PIM , pulled the covers off to check the internal fuses (fuses good) . Smelled of fried electronics inside. Had a friend that does board repairs take a look at it and said some capacitors blew and took a chip with them, so it's not repairable.
Currently waiting for a used PIM. Hope this info is helpful to someone, will come back and update once I install the used PIM.
It would be great if you could post pictures of the PIM being disassembled. Many PIMs are "modular" and the DC-DC converter is on a separate board. Not knowing the PIM architecture, it is hard to say if the VIN coding would be maintained when the DC-DC board in the original PIM was replaced with a used board from another PIM. Maybe worth a shot if someone knows what they are doing and take all required safety precautions.

Here is a video of a Toyota PIM being taken apart:
 

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It would be great if you could post pictures of the PIM being disassembled. Many PIMs are "modular" and the DC-DC converter is on a separate board. Not knowing the PIM architecture, it is hard to say if the VIN coding would be maintained when the DC-DC board in the original PIM was replaced with a used board from another PIM. Maybe worth a shot if someone knows what they are doing and take all required safety precautions.

Here is what is a video of a Toyota PIM being taken apart:
It dies look like it's on different boards and different sides of the assembly, liquid cooling seems to be sandwiched between dc-dc and motor inverter. I'll take pics and post.
 

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It dies look like it's on different boards and different sides of the assembly, liquid cooling seems to be sandwiched between dc-dc and motor inverter. I'll take pics and post.
Early PIMs had failures due to a leaking gasket that allowed coolant to get onto the electronic components. It would be interesting to diagnose what caused your PIM to fail. I would try to replace just the DC-DC converter and leave everything else original to maintain current VIN coding.
 

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Early PIMs had failures due to a leaking gasket that allowed coolant to get onto the electronic components. It would be interesting to diagnose what caused your PIM to fail. I would try to replace just the DC-DC converter and leave everything else original to maintain current VIN coding.
That's probably a good idea.. to keep the Vin coding .. just don't know where it's stored. The guy that looked at the board said the caps blew and took out the chip. I did take a peek at the boards and didn't see any liquid damage.
 

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That's probably a good idea.. to keep the Vin coding .. just don't know where it's stored. The guy that looked at the board said the caps blew and took out the chip. I did take a peek at the boards and didn't see any liquid damage.
According to STAR, VIN coding on a PIM is permanent. It is likely that you will have problems if EVCM "sees" a different VIN that it is expecting.
 

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Hopefully not, there is a procedure to code the pim to the motor ,even looking at the factory scan tool it shows original Vin and new vin.Vin.. so guess I'll find out in a few days
Do you have access to wiTech? New parts allow VIN coding, but I do not think you can re-code. Reprogramming a PIM is a different operation that allows PIM to "synchronize" itself with Electric Motor. I hope you are successful; this will definitely prolong the life of this bespoke automobile ;-)
 

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... Pulled the PIM , pulled the covers off to check the internal fuses (fuses good) . Smelled of fried electronics inside. Had a friend that does board repairs take a look at it and said some capacitors blew and took a chip with them, so it's not repairable. ...
Think you could get photos? and or be willing to sell me the old PIM, like to see if I could attempt an repair.
 

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Think you could get photos? and or be willing to sell me the old PIM, like to see if I could attempt an repair.
I can definitely take some pictures, the motor controller definitely is still good .. only the dc-dc blew out. What would you be willing to pay for it? Think it can be hacked to run with out the dc dc working.. I have a extra motor and charger be nice for a ev conversion.
On a positive note I installed a used PIM, reset all codes and drove it in the air, no faults ,no need to synchronize anything apparently. Charging up now.. will test drive tomorrow.
I'm in Los Angeles area. Where are you located?
 

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I can definitely take some pictures, the motor controller definitely is still good .. only the dc-dc blew out. What would you be willing to pay for it? Think it can be hacked to run with out the dc dc working.. I have a extra motor and charger be nice for a ev conversion.
On a positive note I installed a used PIM, reset all codes and drove it in the air, no faults ,no need to synchronize anything apparently. Charging up now.. will test drive tomorrow.
I'm in Los Angeles area. Where are you located?
I'm in Seattle area. Yeah photos be cool! Very nice you got it working by swaping it out. I got car here with blown PIM that I will be digging into soon.
 

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THANK YOU VERY MUCH @munsterwrench for experimenting to confirm a used PIM works!!!!!

But one shouldn't really take their time too much, becaue if the car won't charge, the HV battery can self-discharge too low to recharge with the built-in system.

It can even discharge too low to resurrect by dropping the giant HV battery pack, opening it up, & trying to charge individual cells.
 

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True, one thing I did was charge the pack up. In my case I was able charge it about 5 minutes at a time as it would stop charging, had to keep a charger on the 12v as well. Glas I did that, because after I took the PIM out and verified it was bad it took almost 2 months to get a replacement 😅
 
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