Hi all

Sorry for another "won't start" thread but I've looked at the manual and it assumes a certain level of knowledge...

Ride: 1998 grand cherokee, 6 cyl, auto, very stock, 70,000 mile (110,000 kms)

Problem: is intermittent and unpredictable but is becoming more frequent (3 times in last 3 days but only once/month when it first started to happen). I'm now at the stage where I park strategically to allow for a tow.

Symptoms:
Without any apparent reason, when I turn the key to start, nothing happens (no engine crank, no lights on dash, no lights overhead and gauges do not move). It's as if the battery is dead (but it's not). Then if I turn the key back to "Off" and then again to "start", I might be "dead" again or I might hear a fast clicking noise from the passenger side, it sounds like it is coming from the fuse/relay panel down there. The clicking sound is quite fast, say 3 or 4 clicks per second. I then have to switch back and forth b/t "Off" and "start" and do this 4 or 5 times and then it will start w/o any trouble. With what little I know, I'm hoping it is a bad relay and not, as a friend suggested, a confused computer.

Every time this has happened I have been alone and so I could not turn the key and investigate the source at the same time. So I can't find the offending relay if that is the problem. And the manual wasn't much help.

Questions:
1) does this sound like a relay, computer or other type of problem?
2) if relay, is there a particular relay that I should look at? I see from other posts that they are about $9 so I'm tempted to replace them all and be done with it.
3) could it be a bad starter solenoid? I don't think so b/c that would not account for the lights going out
4) In a few other posts I saw reference to "underhood relays". Could this be where the badboy is hiding? If so, where under the hood is it located?

Thanks for your help.

The under hood relays are in the Power Distribution Center. That's a rectangular black box about 4" x 8" next to the battery.
This might be of help, I'm not sure. Jeep Wiring diagrams

Check the simple things first,first thing i would do is thoroughly check the battery cables(negative esp.),check the connections(both ends)/posts etc. as this can cause your symptoms as well.Make sure all is good there and also make sure the battery has good cranking amps and go from there.

This sounds like the classic bad battery connection. Clean the terminals of the battery and cables with a terminal cleaner, a specialized wire brush that sells for $1.98. That should fix the problem. If there is a lot of salts on the terminals, use baking soda and water. Put the whole terminal in a jar of soda water.

Thanks for the guidance. Sometimes the basics get overlooked.

The battery posts were very corroded and when I had the battery checked, the mechanic thought the battery had a bad cell. Luckily it was a warranty battery with half the life left on it. Battery has been replaced. So far so good but it's hard to prove a negative so I will just have to give it some time.

cheers

Do yourself a favor and cover each terminal with grease. I do this to all of my vehicles and i never have corrosion problems... Also, im running a 6 year old battery in my "work" jeep. :/

Well it's been over 2 months now and not one occurrence since replacing the battery and cleaning the cables. It's impossible to prove a negative but I think I can say with confidence that the problem was either a bad battery cell and/or corroded cables. Thanks everyone for your help.