My Jeep is Mad at Me :(

**cubewhiz** · 08-03-2010, 04:43 PM

It spit these codes at me:

12 = Battery disconnect
I believe my battery is connected just fine. The Jeep starts right up.

33 = Air conditioning clutch relay circuit
I don't even have air conditioning!

21 = O2 Sensor stays at center or O2 Sensor shorted to voltage
What the hell?

15 = No VSS signal
This one I believe. The speedo housing is in wrong.

17 = Engine is cold too long
That's bull.

55 = Completion of diagnostic code display
Thank you.

Is it possible that #15 is causing these other codes to show up and the computer is just confused? If I fix the VSS, do I need to disconnect the battery to reset the memory or will the computer realize the problem is fixed?

Thanks.

Gally99 · 08-03-2010, 04:53 PM

My understanding of 12 is just that the battery has been disconnected within the last 50 cycles. It should go away after the Jeep's been turned on and off 50 since the battery was disconnected.
I thought it was a weird code too.

Also, I think 33 always shows up if you don't have AC.

If you search the YJ board for "codes", 33 comes up a lot.

**SpideYJeep** · 08-03-2010, 05:18 PM

12 is also just the starting point, will always come up.
17 might mean that your Tstat is opening before the engine comes to operating temperature; this could lead to lower than normal performance, poorer than usual emissions and fuel economy.
Diagnostic Trouble Codes

**cubewhiz** · 08-03-2010, 05:41 PM

What would cause the t-stat to open early? I just replaced it a couple months ago.

moonshinefuel · 08-03-2010, 07:40 PM

What rating thermostat did you put in it?

Mark05059 · 08-03-2010, 07:58 PM

if your getting up to operating temp then change the temp sender for the computer.

**cubewhiz** · 08-03-2010, 08:27 PM

Quote:

Originally Posted by moonshinefuel

What rating thermostat did you put in it?

192 degrees. It does get up to temperature when it's supposed to.

**idaholtby** · 08-04-2010, 12:36 AM

Cube...
If you are getting to the proper operating temp, and you are still getting code #17, then (as previously suggested) replace the coolant temp sensor on the thermostat housing. Either it is bad or you have a bad connection to it. It's sole purpose is to let the ecm know when you are at proper temp so that it will then run out of closed loop.
As far as #21 goes, how old is your O2 sensor? If it has been a while, then inspect the wiring to it and then replace it if wiring looks good. Other things such as an exhaust or vacuum leak can cause erroneous O2 readings, but yours reports to be stuck and not changing readings. Which likely means the sensor is bad or the wiring is suspect. (O2 wiring can get burned on the exhaust or entangled in the front drive shaft.)
You already have the VSS figured out. You have to disconnect the battery for a spell to clear the codes to see if any of your work has fixed each issue.
Good luck.

sloan74 · 08-04-2010, 06:59 AM

12, 33, and 55 you get everytime, at least I do because I am always disconnecting the battery lol

21 and 17 are just sensor replacements? Should be cheap and easy for ya man. Hopefully like ida said.

I just did the TPS on mine, threw code 24 at me. It was 34 bucks and was very easy. The 02 sensor is 44 bucks. Both are plug and play, very easy. You need a torx size 20 to get the TPS out (if that one ever acts up on ya - but if it does you will know by driving it lol). I have never had to replace the 02 but it looks super easy. It sticks out like a sore thumb underneith there.

Yeah mud, water, muck, sand gets up in the sensors and over time they go bye bye. You should of seen my old TPS when I pulled it....lol

**Que89YJ** · 08-04-2010, 08:31 AM

Replace both sensors, they are no big deal to replace. It will help the fuel economy too

. LOL
If the diagnostics are actually telling you then its time. x2 with Idaholtby. Check the exhaust manifold for missing bolts or a cracked manifold. Especially in the rear of the manifold. Its a common problem.

**cubewhiz** · 08-04-2010, 05:20 PM

Okay, I fixed the speedometer housing's orientation and now get a signal again. Then I replaced the coolant temperature sensor on the thermostat housing. I disconnected and reconnected the battery and ran diagnostics again. Same 6 codes. I know the VSS problem is solved because my speedometer is reading accurately now. Did the computer just not reset? Do I need to leave the battery disconnected for longer?

I guess my Jeep is still mad at me.

sloan74 · 08-04-2010, 08:58 PM

yeah leave it disconnected for at least 3 beers.

**cubewhiz** · 08-04-2010, 10:16 PM

Quote:

Originally Posted by sloan74

yeah leave it disconnected for at least 3 beers.

I'll try it.

dagoober · 08-04-2010, 11:06 PM

i just took out my check engine bulb. now when my jeep gets angry the horn just starts going off all on its own. then i give it a pat on the dash and tell it that its a good jeep and it calms down.

how fresh is your battery though? i had some old junk one that was dying out and the jeep did all kinds of weird things. i swapped it out and its all fine now. thats what came to mind when i read #12 anyways.

**cubewhiz** · 08-04-2010, 11:21 PM

Don't know how old it is because it was there when I bought it, so at least a year old (most likely much more). I'm trying to hold off on a new battery until I can put a new pair in together.