hi everyone, i always come here when i need some info. but now im in a pickle.

like the title says i have a 2000 xj and i have a constant misfire, my scanner says p0205- injector curcuit open cylinder 5

so far i have tried swaping injectors, the problem did not move to another cylinder. i have traced back all injector wires to check for a short, all wires are good and have continuity. my only thought is that it is a problem within the pcm.

the only issue with the whole jeep is this constant misfire, there are no other problems i have noticed, please help!!

so my question is, what would you check/ do next? replace the pcm? also where can i find one, i have looked at ACE on ebay and when searching for reviews on google it sounds like a scam.

 

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I'm no help..just learning. If a new PCM fixes it, crack open the old one and check if one of the 6 transistors that control the injector current is shot.

 

P0205 - Cylinder 5 Injector Circuit Malfunction

Article by

Dale Toalston
ASE Certified Technician
OBD-II Trouble Code Technical Description

Cylinder 5 Injector Circuit Malfunction

What does that mean?

P0205 means that the PCM detected a fault in the injector or the wiring to the injector. It monitors the injector and when the injector is activated, the PCM expects to see the voltage pulled "low" or close to zero. When the injector is switched off, the PCM expects to see a voltage that is close to battery voltage or "high". If it doesn't see the expected voltage the PCM will set this code. The PCM also monitors resitance in the circuit. If the resistance is excessively low or high it will set this code.

Potential Symptoms

The symptoms for this code will likely be a misfire and a rough running engine. Poor acceleration. The MIL will also be illuminated.

Causes

The causes of a P0205 engine light code could be any of the following:

Bad injector. This is usually the cause of this code but doesn't rule out the possibility of one of the other causes
Open in the wiring to the injector
Short in the wiring to the injector
Bad PCM
Possible Solutions

First, using a DVOM check the resistance of the injector. If it isn't within specs, then replace the injector.
Check for voltage at the fuel injector connector. It should have 10 volts or more.
Visually check the connector for damage or broken wires.
Visually check the injector for damage.
If you have access to an injector tester, activate the injector and see if it operates. If the injector operates, then you likely have either an open in the wiring, or a blocked injector. If you do not have access to a tester, swap the injector with another one and see if the code changes. If the code changes, then change the injector.
At the PCM, remove the driver wire from the PCM connector and Ground the wire. (Make sure you have the correct wire. If you're not sure, do not attempt) The injector should activate
Replace the injector

 

correct me if im wrong, the ground wire would be the pink,with a black tracer, and the common wire, dark green with a orange tracer would be ground? so if i disconect the pink and black wire from the pcm, the injector should activate if the jeep is running?

and as far as finding a pcm, any ideas other than the dealership?

thanks for all the input!

 

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Purple XJ
Thanks for the explaination on how the PCM interperates a miss. Is this the only way it does it?
Ron

 

Thanks for all the input! I replaced the ignition coil pack to eliminate any ignition problem, still no fix, I also traced back all wires to the pcm for a third time, still couldnt find any issues. I ordered a new pcm so hopefully that's the fix.

Ill update and let you guys know what happens!

 

update! i installed a new "refurbished" pcm and it turns over but dosent start, i did some quick reasearch and im going to look in to the asd relay and make sure the pcm is getting power

also my gauges dont move when i turn the key to the on position, and the CEL light does not come on when the key is turned.

anyone have ideas on what else i should look into?

is it possible that the pcm needs to be reset in any way since it was disconected from the jeep?



all input is appreciated!!!

 

was it starting and idling before new pcm?

 

Yes is started and idled with the exception of the one cylinder misfiring

 

Put the old PCM back in and tell us what happens.
If it runs then I think we all know what the answer is ..... I hope who ever you bought the PCM from has a good return policy .......

 

Well when I had that whole misfire thing I tried everything and it turned out I had a cracked head. Put a new/used motor in and BAM! Works great haha. Just throwing that out there in worst case scenario. They put a crappy head in the 2000 and 2001 that is why I am letting you know since you have a 2000.

 

Ill put the old pcm in today after work and let you know what happens. And about my return policy.... I only have an exchange return or ebay buyer protection.. whatever that is.

And I hope it isn't a cracked head. That would be my worst nightmare. Although im almost positive it's something electrical

 

ok so i get in the jeep today after work and turn the key and it starts and sounds like there is no misfire! the CEL comes on and the jeep sputters and dies. i try to start the jeep again and the electric fan comes on, nothing else, no gauges, nothing. it turns over but dosent catch


so i check the code and it was P1694
something about no communication to the pcm?
and my odo reads no bus.




i decided to swap the old pcm back in and she starts right up with the same CEL saying fuel injector 5 open curcit


my guess is that i got a bad pcm?
also when the jeep did start with the "new" pcm the oil pressure was extremly high, almost maxed out, not sure if it had anything to do with it but i figured i would mention it anyways.



thanks again for all the help!!