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Topic Review (Newest First)
03-05-2012 03:15 PM
coachsamd Ok RUBI thanks again for your help. I did replace that harness once before about a year ago. I will follow it down and see if I can find something. Thanks again!!!
03-05-2012 02:15 AM
RUBI 4 MY MRS Sounds like the wires are damaged & shorting out. If the br/lb wire is grounded (shorted to ground), it will start in any gear. If the violet/white wire is shorted, the fuse will blow as soon as you turn the key to the on position. If the violet/black wire is shorted, the fuse will blow when you have the key on & shift into reverse. It seems like either all the wires may be shorted or the br/lb + one of the others depending what causes the fuse to blow. Follow the wires from the switch along & look for damage. It is most likely shorted under the jeep & probably before they join the main harness.
03-04-2012 08:00 PM
coachsamd Ok here we go again. I replaced the neutral safety switch it still starts in reverse and drive. My reverse lights don't work and checked the fuse to the back up lights it was blown. I installed another fuse and it blew. The jeep starts fine. I tried to adjust the shifter cable and it still starts but no reverse lights. Is it possible I have a short or grounding problem? Thanks for your help!!!
02-27-2012 11:26 PM
RUBI 4 MY MRS When you get under there, check the wires, they could be damaged but it is probably the switch. You might get the same condition if the brown/light blue is grounded. You can further check the switch by seeing if the back up lights come on when in reverse & go off in other gear positions.
02-27-2012 10:15 PM
coachsamd It does start in reverse and drive. I went ahead and bought a new switch and will install soon. Thanks for your help.
02-26-2012 03:27 PM
RUBI 4 MY MRS P1899 (M) -- P/N Switch Stuck in Park or in Gear -- Incorrect input state detected for the Park/Neutral switch (3 or 4-speed auto. trans. only).

Jeep Grand Cherokee WJ - Diagnostic Trouble Codes

Taking a shot here. Maybe the switch is "stuck" in the park (or neutral) position. Can you start it when its in gear(D or R)? If so you can remove it & either free it up or replace it.
02-26-2012 03:10 PM
coachsamd I have a check engine light on my 98 jeep wrangler that is reading code p1899. I know it has something to do with the park neutral safety switch. It starts fine and runs fine. Does anyone have any suggestions? Thanks.
01-11-2012 09:00 AM
jjusagal Our 2001 Wrangler having recurring check engine light on problem. Thanks for some of the tips here. Our latest apparently throttle sensor. Hoping that's the last and we can get back to the fun stuff.
11-30-2011 10:01 AM
Marc House
Engine light codes

I have codes P0132 an P0133 does anyone know the meaning an how do they reset???
04-16-2011 12:53 PM
Griffmeister Quick update - let tank run to empty, filled with gas from Shell, everything is back to normal I guess? No more Racetrack...
04-15-2011 07:55 AM
Griffmeister Got it tested, it's throwing the code p0431. Is this something I can fix on my own or should I take it to a shop? Im a newber when it comes to fixing my Jeep but I have a pretty good mechanical understanding. Found this on an OBD site:

What does that mean?

Basically this means that the oxygen sensor downstream of the catalytic converter on bank 2 is detecting that the converter is not working as efficiently as it should be (according to specs). It is part of the vehicle emissions system.


You will likely not notice any drivability problems, although there may be symptoms such as a rough/hard idle when cold.


A code P0431 may mean that one or more of the following has happened:

The catalytic converter is no longer functioning properly
An oxygen sensor is not reading (functioning) properly
There is an exhaust leak
Possible Solutions

Inspect for exhaust leaks. Next step is to measure the voltage at the oxygen sensor on Bank 2. In fact, it would be a good idea to test each oxygen O2 sensor while you're at it.

One thing to note is that many vehicle manufacturers offer a longer warranty on emissions-related parts. So if you have a newer car but it's out of it's bumper-to-bumper warranty, there still may be warranty on this type of problem. Many manufacturers give a five year, unlimited mileage warranty on these items. It's worth checking into.
04-14-2011 04:24 PM
Griffmeister great, thanks!
04-14-2011 04:20 PM
scgeek12 autozone will read the codes with an OBD2 reader free, i get my codes read from them, then go to pepboys and get parts lol
04-14-2011 04:15 PM
Griffmeister Check engine light just popped up on my 06 TJ. I ran the diagnostic test (held odo and turned key). I got the following messages:

5 of 5.1
bus b8
Panel Open

I had to do it twice, the second time I just took a video clip of it with my iPhone. Finally that things has proven useful instead of a distraction!
08-01-2010 01:03 PM
JDsDream Was the fluid in the radiator possibly a mix of coolant and oil? What does your oil look like? If you can't tell the difference between them, then it is either a leaking or blown head gasket or you have cracked the block. Also recheck your plugs and see how badly they have fouled since replacing them.
08-01-2010 11:40 AM
knutty OK so changed spark plugs reset engine light went off, drove 80 miles radiator cracked cylinder misfire came back and the code changes every time its reset to p 0304 , p 0302, p 0301, p 0305 it flip flops back and forth those codes? Then i got the gas cap code switch the gas cap it seems to have done the trick.

why did my radiator crack? it looked bad inside it was brown. a mechanic told thats a sign of the jeep being mistreated or beat to hell on a trail? he wants to replace water pump, alternator, and thermostat. anything else he should replace or should i hold back on anything if the work fine?

Is a cylinder head cracked?
07-27-2010 10:27 AM
Brad[LK1] i think that's a misfire code...maybe start with a tune-up and go from there
07-27-2010 10:21 AM
wrangler sport 01 code

p 0300
what should i start with?
03-29-2007 10:15 PM
Rawkon what code did you get?
03-29-2007 10:02 PM
gamecock22 Thank you exactly what I was looking for!
03-29-2007 09:49 PM

look at post #5

you should be all set
03-29-2007 09:41 PM
check engine light

I hate to repost something that has been up here before but I'm having a hard time finding the thread. I have a 2002 wrangler sport 4.0 and the check engine light recently came on. I don't want to pay $70 at a stealership so they can tell me what is wrong with it. Is there a way to check the check engine light code from the dash board. I thought I read something about pushing in the trip odometer button holding it, and it would read it out. Thanks for the advice in advance.

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