jeep-dad

Hi everyone I have a 1999 cherokee that was running up until I replaced my battery and now the jeep won't start. It just cranks and cranks. It will turn over with starting fluid, but then the horn honks and honks - what is going on???

Thank you for the help,

Brian

Veeb0rg

Sounds like its got a car alarm either factory or aftermarket.

RockyMtn96XJ

So the alarm is preventing the engine from starting? Is that what's going on?
Are all of the wires back connected to the battery? Maybe there is a small one dangling that was missed being reconnected....

UKXJ

Alarms/immobilizers really don't like being interfered with, which includes disconnecting the battery.

No harm in checking for a disconnected wire but what, apart from the battery, would you disconnect to replace the battery (of course, I have no idea may be tacked onto either/both your battery clamps.

If it's aftermarket, I'd be inclined to remove it completely.

zs&tas

Does it have the remote unlock fob ? My car won't start unless I have literally just unlocked it. 97 zj

UKXJ

On the other hand, I rarely lock mine, if/when I do always use the key & they've always started.

jeep-dad

UPDATE: I have spent many days under my jeep and have learned a lot. Thank you all to those who have offered their advice - its worse than I expected. The previous owner re-wired the CPS into any oxygen sensor so it plugs into that and no longer is plugged into its usual place by the manifold on top of the engine. There is a green wire that fell out and now I think I am going to have to re-wire the CPS and pigtail. When we purchased the jeep, it drove fine and made it about 100 miles back to my home in Ambler, PA. I have already re-wired the fuel pump and now have to figure out who to re-wire the CPS so it plugs into the correct plug on top of the motor - any and all help would be greatly appreciated.

Brian

lawsoncl

Huh? I can't see how plugging the CPS into the O2 sensor would ever work in the first place??? You sure that's what you're looking at?

If this was an old Renix Cherokee, I would have said it had the wiring harness bypass installed by the dealer, but you said 1999.

zs&tas

Mine dosnt work with out a crank sensor ? For sure. I do t know how the early Xjs are wired though.

bigdave2541

Girls in your city for night

UKXJ

I'm still trying to get my head round how it was fine - 'til the battery was replaced.

Now Jeep connectors are a pet hate of mine, but they do mean you'd have to try very hard to connect anything wrongly. I fear the answer here is a repeat of the fuel pump exercise: study a wiring diagram (must be for your year/model) & be prepared to start from scratch. Like you said, worse than expected.

awg

have we established that there is spark, fuel pressure, 12V at coil. OBD codes etc etc ? (or lack of)

I believe there is a fault finding chart for the immobiliser models in the FSM ?

My 96 does not have a factory immobilizer, but to my horror, I have discovered a mystery box zip tied to my steering column, and I think it may be....and aftermarket immobilizer

zs&tas

Uh oh 😳

UKXJ

My thoughts exactly - but if it's not been an issue so far (probably because it's not been activated) I doubt awg, of all people, need lose too much sleep over it.

Similarly, I've never had a problem with my '98, which has an aftermarket alarm (who knows if it's an immobiliser too?) but I've never risked using it, in fact as it's only when I see the trumpet/horn/siren/whatever that I'm reminded - so I don't even get a reduction on the insurance.