Gentlemen,

 

I'm hoping some brains can help me out with where to look.

 

I have a late AE82 Twin Cam Seca which has an electrical problem. When hooked up I get no dash lights and it doesn't turn over. I don't think the starter solenoid even clunks.

 

Battery voltage is reasonable. I can find 12V at the coil and most of the spots I've tried on the fuse/relay box in the engine bay seem to have power. All fuses are OK. The EFI fuse was blown in the engine bay, but has been replaced. The fuses in the driver's kick panel are OK too.

 

Any particular spots I should check to expedite the process?

 

I've got some wiring diagrams downloaded which I will follow through, it's just a question of getting the time to do it. It's annoying, as this is a late Seca the wiring is different the the earlier Twin Cams. It seems to be more like an AE93 with the fusible links etc.

 

Thanks

 

Mike

Tried getting someone to hold the key on start while you whack the start motor with something?

Not yet, starter is buried under the exhaust manifold and not easy to get to.

 

Initial thoughts are that it's something else as I don't have dash lights, but I suppose it could be more than one problem.

Tried a jump- or clutch-start? You can have ~12V at the battery but if it can't supply any load then everything will just die in the arse and not even provide enough juice to light the dash up, let alone click the starter.

Cheers. I'll try a jump start.

 

I don't think I've ever come across a car that won't even light the dash. This is with the battery straight off the charger before trying to start. Maybe that has thrown me. No harm in trying to jump start. Clutch start isn't an option, it's at the bottom of a hill :)

Push it up the hill slightly and then clutch-start in reverse :P I've done that several times in my driveway :D

You say that you are getting 12v at the coil, what else is getting powered?

 

 

was it running ok beforehand?

did you change/play with anything before it died?

No such luck on previous knowledge. I bought it cheap as it didn't work. The guy claimed it had been running just the week before. The battery doesn't seem to hold charge particularly well, so Hiro's suggestion could be a good one. I was just surprised it almost meant no dash lights.

 

Haven't tried again with it yet. It's been too cold and wet to work on cars outside :)

Definitely grab a known working battery from another car.

 

If you've blown the edu fuse, could the dash fuses be gone too?

 

Could be a Dodgey key barrell going to ignition.

 

Try powering the starter directly with some jumper cables. Be careful though, it's easy to ground the positive down there.

 

Make sure you check fuses with a multimeter not just by sight. Also check if you have power to the battery side of the fuse.

 

Check ecu is getting power on ignition also.

Excellent suggestions. I was only checking fuses by sight, but they're fair points. When this weather clears, I'll get into it :)

So it turns out the ALT fuse was gone on this one. I thought I'd checked it with a meter rather than by sight, but obviously I hadn't.

 

New fuse and the dash is now on and it will crank over. It's not starting though, so on to the next round of troubleshooting!

 

What's the first port of call, should I just jumper the diagnostics port and go from there?

Sounds like the starter would be the next thing to look at. Try see if you can throw the starter with leads/wires or clutch start it

If it cranks the starter is OK.

 

Jump the diagnostics and see what's in there.

 

Pop a plug or 4 and see if you have spark, or just use a timing light.

 

Can you hear the fuel pump?

 

If you crank it with a plug or 4 out, can you smell raw fuel.

 

Its either missing fuel or spark.....

Yeah, usual stuff then. I can't hear the fuel pump, but then it's in tank and under the floor so that didn't surprise me. I'll check it out. One step at a time :)