My 1996 f350 7.3l wont start. The battery power is good, panel lights come on bright then fade. Wait to start light comes on then within seconds goes out as if it lost power. Clicking noise coming from the relays(fuse box). What I believe is the power mod located to the front left of the fuel filter clicks on and off with the wait to start light. The starter clicks as if it is nor receiving enough power. I have checked the fuses and relays now I am lost. Can any one help. Thanks Scott

 

Well, no, your battery power is not good! Those are all the symptoms of a dead battery. Perhaps, if the battery really really really is good, it's loose battery clamps or something. Did you check *both* batteries?

Duncan

 

Also check the hot lead to the starter for corrosion/looseness.

 

Thanks for the reply. I checked both batteries and have tried to jump it. The battery gage reads well within the normal range when I try to start it.

 

hot lead is clean thanks

 

The gauge is completely meaningless in this context. I could hook up 8 AA batteries in series and get the gauge to read right, but I'm not going to start the truck with them!

If those are the original batteries there's no need to even consider any other possibility, they're done. If they're recent-ish then you should be looking at connections that could be bad, but I still think the batteries are at least flat, even if they're in good condition and can live again with a recharge.

A diesel engine takes a whomping amount of current to turn over, against all that compression. The glow plugs take a whomping amount of current to heat up for 2 minutes after you turn the key on. Tossing on your average skinny jumper cables from a Honda and trying to start it isn't going to cut it. You need really good high-amperage cables, and you need to leave them connected, with the running car at elevated idle for several minutes before you even think of trying to start the truck. And if that works, what you really need to do is get the batteries on a charger for a few hours at a minimum, rather than making your alternator do all that work of taking two big batteries from flat to fully charged.

Duncan

 

Smells like a bad cell in one of the batteries. Immediately after charging the voltage looks good, but that cell holds only a minor surface charge that quickly vanishes, leaving the battery at about 11 1/2 volts. The bad cell also prevents charging the other battery to full voltage. If your batteries are fairly new, check the voltage of each cell with a voltmeter (meter clipped onto a pair of screwdrivers dipped into each cell and between the end cells and the adjacent post will do it). If there is only one bad cell, you could consider replacing only that one battery.

 

just a bad cell in the batt. Thanks to all who replied.