HELP! 98 XJ WON'T START.... NOT CPS

i just bought a 98 cherokee sport 4.0 4x4 auto. it has been sitting for 6 monthes. it was started and ran fine 2 months ago. now it will not start. lots of problems, i'll start from the begining.

dead batery-installed new one.

engine won't turn over and reverse lights won't come on.- i figured its the neutral/reverse safty switch, so i pulled the relay in the engine bay and used a wire to jump it and the engine cranks perfectly.

now the kicker: no spark- (i have another 98 cherokee that runs fine, so the following parts came off it to get this one running) replaced the crank position sensor, no change. replaced the cam position sensor, no change. checked voltage coming to cam sensor, no voltage at any of the 3 wires. checked wires going to coil, no voltage in either one, no pulsing ground signal on either one. all wires were checked with ignition on and with engine cranking and not cranking.

not sure where to go next? computer? ignition switch?


there is no "check engine" light
turning the key to "on" seems to make all the other electronics work properly.
power door locks do not work at all


any ideas greatly appriciated.

Try the key on-off 3 time and see if a code has latched. I have the pretty much the same problem except I have voltage to the coil but no pulsing.

update

i just switched out the ignition switch, no change.

i tried the code reading trick with the key. the gauges cycled through as they should, but no code came up.

Pretty much where I'm at - read my post.

Distributor cap maybe? I would check all wires from plugs back.

Note you can't do the key trick on a 98.

Did you try using the power door locks with key in ignition and door open? If so, I think the power door locks are disabled in this situation to help prevent keys from being locked in the car.

As far as your issue, did you check all the fuses and relays...both at the passenger side kick panel and under the hood (near coolant reservior)?

Maybe one of the power fuses is burnt out or maybe a relay is not 'clicking'.

good luck.

Ah, you did check all of your fuses didn't you? Sounds like you're having lot's of electrical problems. Could be corrosion in some of the various connectors.

When you bypassed the relay, you took a lot of other stuff out of the circuit. Did you try bypassing only the NSS?

try to jump the relay with the key "on". If it starts it is the NSS. You can bypass it also...you just won't have any backup lights.

thanks for all the responses, i got it started. it turned out the be the ecu. i swaped one from my other jeep and it fired right up. i'm still having problems with the starting circut. its acting like a bad NSS, but when i bypass it, it still won't start. all relays and fuses are good. any ideas?

No ideas (yet)...but wondering why your 'puter went out...struck by lightning? What kind of voltage is your alternater putting out?