tkotitan
NAXJA Forum User
- Location
- Vermont, USA
My rig: '94 XJ SE 2dr 5spd 4wd selec-trac 168k miles. I guess I'm not allowed a signature yet.
So I ran the codes today and see I have three issues. Since it is an OBDI, things are simple, but I am wondering if my friend who is handy with electrical can help me fix some things before winter.
The codes I got were
12 Battery or computer recently disconnected
21 Oxygen sensor signal doesn't change (stays at 4.3-4.5V). Probably bad oxygen sensor [I assume for newer jeeps like mine is sticks at 0.45v?]
33 Air conditioning clutch relay circuit open or shorted
35 Cooling fan relay circuit open or shorted (there is an alt code for this but this explains why my blower only runs on high)
55 done codes.
Code 12 I did intentionally, resetting my computer since I am running an experimental HHO kit. Not sure how long this code stays since I did that a few hundred miles ago. So this is not an issue.
Code 21 may be the new one. The check engine light came on for the first time today. I switched off my HHO kit because it looked like it wasn't running, but my ammeter is dead and I may have just tripped the auto-reset breaker. Maybe I finally killed the O2 sensor, or it could have been always dead. I was driving it with hard starts for fun today, and with no HHO it would have noticed more unburned fuel. If it locks the O2 sensor at nominal then I am fine with that.
Code 33 A/C circuit. I am curious about this. My compressor will not take any charge. It was a replacement used part that lasted a summer than locked up, which is what happened to the previous one. How would I fix this, and could it be killing my compressor or am I putting the cart before the horse here? I barely need the A/C since I live in VT but for traveling in the summer it is nice.
Code 35 fan relay. My blower only blows when it is set to max. Otherwise it blows a tiny bit on all settings. Would be nice to fix this to stay on top of it in case it blows before winter.
I took the door switch out a couple years ago because I had another wiring problem - the dome light was on all the time flickering. I burned my fingers getting the bulb out. The switch may not have helped anything. I used to never lock the wheel (and got in the habit of starting it without the key) but when this problem started it was draining and so when I started locking the wheel it stopped draining. Not sure if the bulb was on when the wheel was locked but I could get a bulb and see I guess.
So I need a wiring overhaul here. Problem is my mechanics are good wrench-turners but bad with electrical. My friend is good with electrical and can help me on weekends. We have taken apart the dash once before so it's easy.
Any clues on how we would work on the AC clutch, or the fan relay? or otherwise get rid of shorts? At 168k you would think some things are starting to go.
So I ran the codes today and see I have three issues. Since it is an OBDI, things are simple, but I am wondering if my friend who is handy with electrical can help me fix some things before winter.
The codes I got were
12 Battery or computer recently disconnected
21 Oxygen sensor signal doesn't change (stays at 4.3-4.5V). Probably bad oxygen sensor [I assume for newer jeeps like mine is sticks at 0.45v?]
33 Air conditioning clutch relay circuit open or shorted
35 Cooling fan relay circuit open or shorted (there is an alt code for this but this explains why my blower only runs on high)
55 done codes.
Code 12 I did intentionally, resetting my computer since I am running an experimental HHO kit. Not sure how long this code stays since I did that a few hundred miles ago. So this is not an issue.
Code 21 may be the new one. The check engine light came on for the first time today. I switched off my HHO kit because it looked like it wasn't running, but my ammeter is dead and I may have just tripped the auto-reset breaker. Maybe I finally killed the O2 sensor, or it could have been always dead. I was driving it with hard starts for fun today, and with no HHO it would have noticed more unburned fuel. If it locks the O2 sensor at nominal then I am fine with that.
Code 33 A/C circuit. I am curious about this. My compressor will not take any charge. It was a replacement used part that lasted a summer than locked up, which is what happened to the previous one. How would I fix this, and could it be killing my compressor or am I putting the cart before the horse here? I barely need the A/C since I live in VT but for traveling in the summer it is nice.
Code 35 fan relay. My blower only blows when it is set to max. Otherwise it blows a tiny bit on all settings. Would be nice to fix this to stay on top of it in case it blows before winter.
I took the door switch out a couple years ago because I had another wiring problem - the dome light was on all the time flickering. I burned my fingers getting the bulb out. The switch may not have helped anything. I used to never lock the wheel (and got in the habit of starting it without the key) but when this problem started it was draining and so when I started locking the wheel it stopped draining. Not sure if the bulb was on when the wheel was locked but I could get a bulb and see I guess.
So I need a wiring overhaul here. Problem is my mechanics are good wrench-turners but bad with electrical. My friend is good with electrical and can help me on weekends. We have taken apart the dash once before so it's easy.
Any clues on how we would work on the AC clutch, or the fan relay? or otherwise get rid of shorts? At 168k you would think some things are starting to go.
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