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Emergency help - Car won't start


TLicense

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All,

 

I've just driven the car up to Leon's. Drove from Leon's to central Milton Keynes, parked up for a couple of hours, then drove all the way back to Oxford. I just went to start the car again, and it won't start.

I can turn the alarm on/off. When I turn the key the lights all dim, and I can hear what sounds like a relay clicking on and off. But that's all. I can't hear the starter engaging, and it's certainly not trying to turn. Oh yeah I can hear the fuel pump running.

I've pluged a laptop into the AEM and can see that there's 11.5 volts output from the battery.

I've tried disconnecting the battery and checked all the main fuses in the engine bay. What's next on the check list?

 

Is there any way to check the alarm? It's a Toad A?? (Can't remember but it's the CAT 1 selling for about £350 if I remember rightly)

 

Any help at all would be much appreciated

 

Regards

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Agreed, it sounds like a flat battery. Try the wipers and the electric windows - if they are sluggish you've found the prob. Battery voltage should be 12.5 to 13.8v across the terminals. Wierd things start happening when the charge gets low - flashing/glowing lights on the dash, some systems working and others not, that sort of thing.

 

-Ian

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Sounds like a flat battery. When you were last driving it did you notice anything odd with any of the dash lights coming on at all?

 

BTW last time I collected my car from Leons it broke down about 30 miles away. The battery had run down, both terminals were lose and fell off when touched and the alternator was also shagged.

 

Mine would start with a jump start but as the battery wasn't charging the engine wouldn't run and we had the AA battery pack resting on top of the engine so I could drive off the M1.

 

Shortly before it died the ABS and some other lights started flickering on.

 

The 12.8 volt should be enough to start it. Can you check the level of the electrolyte in the battery.

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Cheers Jagman,

 

I'll give rocking the car a little, a try. The inhibit switch was left on the car, but the wiring is under quite a bit of strain, so will relieve that first thing in AM and see if that's worked it's way loose at all.

I tried disconnecting the switch before, and got exactly the same thing happen. Didn't immediately attribute it to this as it was still connected, but like I said will have a play with in the morning.

 

Strange one though. Leon tried by-passing the inhibit switch but it wouldn't have none of it. I was going to get Matt H to take a look at it next Saturday. Guess it shoulda been this one.

 

Thanks again

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Originally posted by TLicense

I'm getting 12.48V.

 

Battery voltage isn't a good indication of battery condition. You really need to 'drop test' the battery to test the amperage or current.

A battery with a duff cell could well show 12.5V on a multimeter, but would not produce enough current to start a car.

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Gordon,

 

Agreed, but Jumpstarting should have got the car started if the battery had been duff.

 

 

Matt,

 

I guess that'll be the lump tie-wrapped to the gearbox support. It's kinda the reason why I was going to come see you next Saturday.

Leon has tried to by-pass it before on a previous conversion but the sulotion unfortunately elduded him. Any ideas chaps???

 

Regards

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there is a 7.5 amp fuse in circuit that supplies the park/neutral switch and then on to the starter relay contact 1 then fron contact2 to earth via theft deterrent unit, to bypass the p/n switch you could run a cable from a 12v supply to contact 1 of the starter relay and try it, then run an earth to contact2, or just put your hand on the relay and feel if its working or trying to

also if you short out contact3 to 5 that should cause the starter to crank proving the main 50 amp supply fuse, hth

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Cheers for all your advice chaps, I'm still struggling with this. Basically I'm no auto-electrician and I feel like I'm pissing in the wind here.

 

OK I've got the electrical manual from MKIV.com but I have no idea what the hell I'm looking at.

 

Jagman, could I ask to give it to me in layman terms here, from I understand so far.....

 

I need to prove that current is going to the starter motor right? The current to the motor is controlled by the starter relay. I need to check that there is current going to that relay.

I can by-pass the relay (I presume with the ignition switch on :p )

by bridging terminals 3 and 5 right?

If I run 12 volts to terminal 1, and then earth terminal 2, this should effectively by-pass the park/neutral switch yeah?

 

Could someone actually point me in the direction of where this relay is? I presume the drivers kick panel?

 

Adam,

 

Yeah any help would be good. Problem is this doesn't appear to be intermittant at all. First time it happened was yesterday, and hasn't started since :mad:

 

All help greatly appreciated,

 

Tony

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Only if you know how to use it! :innocent:

 

Does the relay make a clicking noise/feel when you try to engage the starter?

 

Can you get access to the starter motor itself? - If so, can you tell me what power supplies are on the starter solenoid? - Can you also check that all the connections are tight whilst you're there...

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OK chaps. Mid-day update.

 

My dads mate who is a mechanic has just poked his head around and helped me out for an hour or so. Here's the run down.

 

We can get the starter motor to fir by unplugging the wire that sends a signal to it and connecting it directly to the battery. With the ignition on the car will run.

 

If we connect the signal wire, and fire the starter with a splice direct to the battery, it will turn over but won't start.

 

He thinks it's probably one of two things.

 

1. The immobiliser driver for the starter circuit is knackered (As I said the immobiliser is a Toad Cat 1. 1 year old not had a single problem with it before this)

 

2. The park/neutral switch has knakered itself.

 

I really think I need to by-pass the park/neutral switch somehow, as I recon it probably the origin of all things evil :devil:

 

What do you chaps think?

 

Oh yeah, nothing was done at Leon's yesterday. Just picked up some bits, nothing fitted.

 

Thanks for all you help so far chaps....

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