p38 battery issue

hi guys
i am new to this forum and i have come with a problem that is causing us stress. We have a range rover p38 1996 4.6 auto come into us. The fault is the vehicle wont start as soon as you turn it of and go to restart its like you have a flat battery. The battery is brand new and the starter motor was charged by the customer.

We have checked the charging rate 14.volts. jump start and it runs fine until you turn it off.

Have you checked for bad earth or bad battery connections?

I agree with Oval. Check the bonding strap that connects just below the alternator.

How long do you leave it before a re-start is attempted? If overnight, probably the BECM is not going to sleep, if a short time, your new battery is duff or you have an alternator fault.

not just the earth stap ....... I had a positive connection that was corroded inside the insulation ..... same effect.

bhamrangerovers said:

hi guys
i am new to this forum and i have come with a problem that is causing us stress. We have a range rover p38 1996 4.6 auto come into us. The fault is the vehicle wont start as soon as you turn it of and go to restart its like you have a flat battery. The battery is brand new and the starter motor was charged by the customer.

We have checked the charging rate 14.volts. jump start and it runs fine until you turn it off.

Click to expand...

are you a garage or d.i.y?

the starter motor was charged by the customer.

Click to expand...

Did you mean "changed"?

If so that's where I'd start. New starter motor or 2nd hand / recon? One thing I've learned after many years of tinkering with cars is NEVER leave a 'new' component out of the fault diagnosis flow!

Leave your multimeter connected up whilst attempting to crank it - what voltage drop is it showing? Try it with just battery, then with the jump. Big voltage drop with battery, but small one with jump, suggests the problem lies between the battery posts and the terminal (dirt/corrosion/contaminant?). Same drop with either suggests problem is further downstream.

EVERY British-made vehicle I've ever owned has had problems with earth bonding! Including an old Rolls Silver Shadow... Which has a +ive earth system. Ask me how I found that out....