CHECK ENGINE LIGHT code 12 & 14

[Howdy]

I don't know what kind of Jeep and engine you are running, but I have a list of codes for a TJ which also seem to be the same for my Mopar MPI.

12 is Direct battery input to PCM was disconnected within the last 50 Key-on cycles.

14 is MAP sensor input above or below acceptable voltage.

5 volt output to MAP sensor open.

It also says that for #14 "Check engine lamp will illuminate during engine operation if this Diagnostic Trouble Code was recorded."

[coachgeo]

I have a 97 TJ... with the above mentioned error codes according to the odomiter error code reading method.

Other problems came about at same time. A tick tick tick tick.. metal to metal that makes me nervouse as shit... but it dissapears and when it does my speedo drops to zero and performance goes up above normal.... weireeeedddd

Other related... or not? issues.. Cracked Exhaust manifold like thousands of others. Speedo been givng me fits for a while. Reading info seems to say its a short problem and not big issue.
Also, I am assuiming a Cat converter going out.... at times it feels like someone threw out a huge as anchor.... for a few seconds. From reading I determined its back pressure from a clogged Cat.. (some crap blocked the exhaust for a secod or two) and that as the crap all finally blows out its will be fine till I have to get an emissions test.

[coachgeo]

OK... I found the tick tick tick

SHITTTTTTTTTT.... I checked T-case oil.. it was dry... FAWWWWKKK

I put oil in.... it came out bottom of case as fast as it went in the case.

what this has to do with the map sensor I have no idea.. the spedo.... that makes some since..


I now have no transport... the bus stops is about 10 miles from work and a taxi is about a 30 dollar ride... fuuuunn funnnnn

oh well.. new post time...

[LordRatner]

FIX YOUR CAT!!! That huge anchor is indeed your cat, and mine just gave out a week and a half ago, but I was on the freeway with no choice but a tow truck. Not fun.

[coachgeo]

yeah.... guess Ill be fixing lots of shit at once now...

Cat
Tcase
New exhaust

Any upgrade ideas while im underthere...

I have a 2000 model exhaust manifold already just needs installing..

I was considering an axil upgrade... guess thats out now... only so much $$$ (I have a 44 stock rear)

What if I decided to go from daily driver to a dedicated trail rig... how does it affect what I do wiht the Cat.. Tcase. and exhaust, or does it?

[coachgeo]

NEW TO THIS THREAD? Read FIRST reply from Coachgeo first, then follow thread.

Originally posted by Howdy
......list of codes for a TJ which also seem to be the same for my Mopar MPI.

12 is Direct battery input to PCM was disconnected within the last 50 Key-on cycles.

14 is MAP sensor input above or below acceptable voltage.

5 volt output to MAP sensor open.

It also says that for #14 "Check engine lamp will illuminate during engine operation if this Diagnostic Trouble Code was recorded."

Call me Dumb.. what is PCM... and could my short causing errors to the Speedo be causeing this PCM issue... the map issue too?

[Howdy]

Originally posted by coachgeo
NEW TO THIS THREAD? Read FIRST reply from Coachgeo first, then follow thread.



Call me Dumb.. what is PCM... and could my short causing errors to the Speedo be causeing this PCM issue... the map issue too?

The PCM is basiaclly the "computer" that controls everything. All that error code 12 means is that sometime in the last 50 times you have started your Jeep you have disconnected the battery, which led to your PCM not having power at that time till you connected you battery back up again. If you are having problems with your MAP sensor just go down to the local auto parts store and by a new sensor and plug it it and see if that gets rid of that error code. While you are down there buy an extra TPS so if the one you have goes out on the trail you can just plug in your new one. Your Jeep will still run with a bad TPS, but it will just run poorly.