jmrec100

Been working to smog my Jeep. Previous discussions. I had to move it out of the garage for a day. Left it parked and then went to move it back into the garage 3 days later. Won't start. I checked the battery, it was low at 11.5 Volts. Still should have turned over but didn't give it a thought. Jeep elevtrical systems are sometimes rather 'annoying'. So I went and charged it back to 12.5 volts. About 10 minutes , done- Full electrical charge.
During this time, I disconnected the battery. Did so because was charging the battery and had changed out the O2 sensor. It ran like junk and worse readings for smog test with new sensor. One of the post suggested re-learning. Disconnecting the battery would clear out the Computer. Battery was un hooked for a few hours. Hooked it back up, Put a meter on the battery after the charge and see no electrical drain. But still won't start.
Did the code read , 3x's ignition on-off etc. Read code 12 (Controller memory cleared-battery disconnect). 35 and then 55 (end of message)

One diagnostic says code 35 is
either Idle switch shorted-switch input shorted to ground-some 1993 vehicles. What? Mine is 1994. I will check date of manufacture.
Other says Radiator fan control relay circuit-open or short detected in the radiator fan relay circuit.
But this would not cause it to not start? I tapped the starter in case starter is bad. Had that happen before. Nothing. I put the meter at the battery positive post and other lead to ground when I tried to start it. When turn the key, no voltage drop. So seems no current getting to starter or starter is bad?
Other thing I did notice and I was going to check after get this beast smogged. When turning the ignition key, the water temp gauge would peg out when the engine was starting. Then go back to normal. I had asked a mechanic I know and he said it was nothing to worry about at the time. I was going to trace it back when done smogging. But maybe related?
Any suggestions what happened and what to check

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Update : Mfg date 5-94 so probably Not the Idle switch code

jmrec100

I sprayed the starter connections and the ground connection at the battery to the frame. After 2 hours, it started. Took care of the start issue. I'll be checking all the grounds and adding another ground strap to the starter motor. Grounds are an issue with Jeeps. I'll check the code again and go from there.

94JeepCherokeeMan

Yeah, 35 is the cooling fan relay or circuit. Check your fuses. You DO have an auxiliary fan, right? It should kick on after switching your A/C on within a second or two.

jmrec100

I do have an Aux fan. I was working on the smog issue when trying to move it back into the garage. Wouldn't start. So looked at codes. Didn't have a 35 code. I checked all the fuses an all the relays (switched same like relays around). Didn't see a problem. Prior to the no start issue, the fan did work fine. I check that often when driving. Good suggestion./ Will check that out when I work on it.