Hey everyone, I've gained a lot of knowledge from the posts on this forum in the past few years since buying my '99 Cherokee Sport and have never been so stumped that I've had to start a new thread but now that all will change- first post ever on CherokeeForum!

I'm having a no start situation that I believe is electrical. If the key is turned to the "Run" position all of the gauges come live and the car dings at me as if all is well. As soon as I turn the key to "Start" the whole vehicle goes dead- no lights, no power locks, no gauges, nothing! If I wait a few minutes I can repeat the process- turn the key to "Run" and all is normal; turn the car to "Start" and the entire car goes completely dead.

I have replaced the battery (and it reads a constant 12.9 volts). I've replaced the starter. I've inspected the positive battery cable, and the vehicle grounds.

I'm completely baffled as to what has happened to this truck! Please Help!

Thanks in advance.

 

Just guessing here, but I would look at the ignition switch itself. I guess an easy test is to turn the key to on and jump the terminals on the starter and see if it starts. If it does, the your problem is in the switch or the wiring. Also check the relay under the hood for the starter circuit. hope this helps

 

Has the battery been load tested? If so then try cleaning all the grounds thoroughly.

 

Is there a more definitive way that you know of to determine whether it's the Ignition Switch or something else? The starter and battery are brand new and I swapped the relay with one that I know works... and would a bad relay make the entire vehicle lose power (power locks, dome lights, everything!) after an attempt to start?

 

I had a feeling that the battery was down on amperage so I replaced it... that wasn't it. Brand new battery and the problem persists.

 

I would test the battery volts as someone turns the key to start and see if there is a large drop in volts. That, I would think, would be because of a short in the wiring or the switch. I am not one of the experts, you may want to get a second opinion before swapping out parts...

 

Bulkhead connector corrosion.

 

Does the '99 have a security key chip or something like that? Did you get new keys made? I had that happen on a GM van. Had a "spare" key that didn't have a chip, when I put it in, it fit perfect and you could turn the key but everything went dead when you tried to start.

Could be the ignition switch or the wiring to the starter? Remove the negative wire from the block and clean up the connection with a wire brush.

 

No, she doesn't have a security chip. I don't even have remote locks lol.

The wiring to the starter seems fine- no nicks or anything on the cables and continuity is good, and the poles don't seem to be getting crossed. Also, all of the battery connections are clean- just did that when the new battery went in.

 

Would you mind elaborating on this?

 

Can anyone offer an opinion on this? I think BruceB is on the right track, it seems like something might be shorting out, but how can I ring out exactly what the problem is without replacing every part in the electrical chain, one by one until it miraculously works?

I'm sorry, auto electronics baffle me.

 

Definitely a bad connection most likely on the battery, fuse block, starter, or ground wire off the battery. You can't just ohm them out to find the bad one because your not putting high amps through the line which will break a weak connection point. You will need to go through all your connections at the above locations clean them up and put some dielectric grease on them they are the only ones that could kill power to everything after a heavy amp draw. If you had a short you would know there would be lots of smoke and blown fuses. I have this issue on my own jeep occasionally because I am lazy. my battery positive cable is severely corroded key in run everything lights up and looks good turn to start I get a click then loose all power for a while wiggle the battery positive connector to break free the grime and it starts right up. Eventually I will run new cables and clean all the connections but for now I live with it

 

Also just because you cables look good does not mean they are. Take them off and try to bend them if they are stiff then you have corrosion inside the insulation and should consider changing them

 

^ this.
You could be running interior lamps off the battery surface charge which wouldn't require a clean connection.

Do you have a remote starter switch? Its a simple push button switch which connects the starter with the battery. Like this one:

 

DO NOT apply dielectric grease to any ring terminal connection, or any pin connector's pins and pin cavities.