V12 won't turn over/crank
 

Hi,


Just went to start up my 92 5.3 V12 after 3 months in hibernation and it won't start.


Battery is good so it's not that. All electrics work normally.


No click from solenoid


If I have the headlights on and try to start they don't dim so no load going into the starter.


Car doesn't have an alarm or immobiliser as far as I know i.e I just have regular keys


I tried moving the gear selector from park to neutral but made no difference.


Any ideas?


Thanks
Rich

Check the wiring to the starter motor solenoid and the starter relay. If possible, check the connections to the relay, or swap relays.

Check the neutral start switch for power and continuity.

I think relay location moved from back corner of engine bay to radiator top in 1992 but there should still be red/white wire coming up from starter area joins at a male/female spade is quite often the culprit. Might need cleaning up.
You could check starter function via that wire while you're there.

Thank you.


I think it just needs a kick start as it was fine when parked up so a sticky relay is likely to be the cause.

Well the relay is clicking so its somewhere between the relay and starter.
Next step is to get it jacked up and see whats happening down at the starter end.

I could hear the relay clicking but couldnt actually see it. Sounded like it was underneath the ABS unit? on the right hand side of the engine bay near the windscreen.

Also worth checking engine earth strap

Perhaps easiest way is run an additional heavy gauge wire from earth bus bar at firewall to convenient point such as inlet manifold

Careful danger
 

DANGER, DANGER
The buzz bar at the firewall is LIVE not an earth. Do not do this or the car will burn up and the wiring fry!
Greg

WOW!!!! mistaking a Hot + for a _ can be a mess.


I did that. but, got away with merely cooking a pair of fusible links!!!


Soldered in a fresh pair and back where I was.


Case at hand. No start issue. I've one with my Jeep now!!!
May well be a parallel!!


I started with my VOM. 10+ across the posts. Good enough for a barely crank, but not enough to also fire.


Again probed cable + to cable _. Same value. Aha, that means the cable connectors are clean!!


Connected the smart charger. Very low charge measured. Charged slow for hours, Up to 90%. Not good enough, it will get more charge later this AM.


Your Case:


1. Battery charge status? Bare minimum, 12+!


2. Down and under with a jump from the firewall + post. Apply to solenoid small post. Clank and crank? Great, relay and/or wire issue!!


No crank? Apply to big starter lug. Starter spin? Quick as the under sized jump will get super hot, quick. Good, starter Ok, solenoid not.


Report back.


Carl

Pull the relaly, and jump the terminals where the 30 and 87 lugs plug in. Make sure the car is in neutral.

If the car cranks, the problem is before the relay, if it doesn't, check the wiring between the relay and the solenoid, and the starter.

Where is the relay

If it is the same as my 94, it is under the hood, on the right side, and the rear relay.

I said in my prior reply that if it cranks when the relay is jumper, the problem is before the relay. It could also be the relay. You could also try switching the horn relay (the one next to the starter relay) and see if that works.,

All sorted.

It was furred up contacts on the relay. The relay was clicking but the signal wasn't getting out to the starter.

I'm glad it wasn't anything to do with the starter as the starter is impossible to get to!

Sorry, I was responding to a X152 thread, no idea how I ended up here...

I realize this is an old thread, but I have the same car with the exact same issue. Can you tell me where is the starter relay located?

If a V12 (pre facelift, not sure about 6 litre V21 facelifts) in the engine bay, rear RHS just under the gutter, under a plastic cover.