Volvo2.4t

I purchased a 2000 Jeep Cherokee Sport a couple days ago and I have two questions. Please help.

1) I have a check engine light for p0122 p0123 and when I turn the wheel the airbag light will come on and then sometimes go off. Also it has new tps sensor and plug. The vehicle also runs great no stutter or rough idle.
2) My oil pressure gauge does not work and I found a sensor in the picture attached that has nothing plugged in.

PatHenry

That looks like an oil pressure sending unit. The location is strange looking, is the picture taken from underneath?

Is there a plug nearby or wires? The sending unit (I believe it's true for 00) is a single wire into the connector. If the connector is gone you may be able to find one at the junkyard.

PatHenry

That's the sending unit for a 00 XJ. Looks like a match.

Volvo2.4t

The picture is from top down by the oil filter. The harness in front does have plug hanging off that's not plugged in. But it won't reach to that sensor.

Volvo2.4t

Would that cause the gauge not to work?

PatHenry

It's not plugged in. There should be a wire with a connector that plugs into the sending unit, look in the general area and see if you can find the connector. Clean it up and plug it in. If you can't find the connector, are there loose wires nearby?

PatHenry

What's holding it back? Is there any "aftermarket" electrical tape or something? Can you re-route the connector maybe?

Worst case, splice in an extension if you have to.

The location of the sender seems weird to me. On my 95 it's up near the filter (way higher up than yours) and on my 00 TJ it was pretty much right next to the filter.
Yours looks like it would be easier to access from underneath - maybe that's just the way a 00 XJ is, I don't know, maybe it was relocated by a P.O.

Edit -- It may be that the sending unit was relocated by a P.O., but why anyone would do that, and then not extend the wiring to the new location, just wouldn't make sense.
What you could do is unplug the sending unit (it just threads in - but be careful not to break it) and see if the plug matches the sending unit... or if you're bold, cut the connector off in preparation to splice in some extension wiring and see if it fits the sending unit, then do the splice.

Regardless, that would be the reason for the gauge not working and how you'd remedy it.

Volvo2.4t

There is a plug near by I will try out when I get home.

Any idea on the p0122 p0123 with the airbag light turning on and off? The tps sensor is new and the plug on it. I visually checked the wire harness but all the wires looked good. Vehicle drives just fine, most threads I read says when tps is bad the Jeep runs rough.

tiger02

Most likely your clock spring in your steering wheel has a loose connection or it's bad altogether. My 99 does the exact same thing now. I fixed it a year or so ago, but when turning right the air bag light will go off only to return when the wheel is straightened back out. The clock spring is a long coil of wire that connects the horn and the air bag as well as the CC buttons if you have that option.

PatHenry

Airbag light is usually clock-spring. It's pretty easy to get to and test, but the part is expensive to replace.

I'm not sure on the codes, there are some guys on here that are very knowledgeable on the ODB2 codes that should eventually jump in here.

Since you're new to the 00 XJ, make sure you familiarize yourself with the 0331 head defect. Early detection makes all the difference with that.

Volvo2.4t

The p0122 and p0123 is TPS circuit high and low. Maybe the clock spring is messing with it?

Also it has 229,000 miles so I'm hoping it's past the head defect point lol

PatHenry

If you didn't use a Mopar TPS, the TPS could be bad out of the box.

Do a test on the TPS using a multimeter (search for testing steps). If it was Autozone special, return it immediately and get a Mopar!

I had a 00 TJ with the 0331 that has over 300k on it and never cracked. The cracking is more to do with luck and cooling system maintenance. Do check if it was replaced (see if it's a TUPY) already and if not, or "not sure", keep a close eye out for problems. Coolant in the oil will quickly destroy the crank bearings (symptoms of this include low oil pressure....) and mean the difference between a $700-ish + a weekend job and a $2000+ + multiple weekends job swapping out the engine.

gat

The photograph seems to be from the vantage of behind the accessories belt and horizontally viewing the block from front to rear on the passenger's side. On a 2001 Wrangler that is the same spot from memory. The connector comes from the firewall and would dangle below the switch a good bit. I'll verify that information on my Wrangler on today.

fb97xj1

That is a possibilty. There is a splice (S111) between the clockspring and PCM that is shared by both the TPS and the airbag circuit. Something about the TPS affecting the circuit. Cant remember the details. The oil pressure switch also shares S111. I cant say what the issue is for yours, but the TPS codes, airbag light, and missing oil pressure switch connection have me curious. I havent dug as far into to the XJ wiring as others have.

Volvo2.4t

I wonder if the plug missing could cause a short. Especially if there is wires hanging from it missing a plug?