wired battery wrong polarity help

[ancol]

hi guys need to pick everyones brains fitted new battery today no probs but like a numpty inadvertantly connected up backwards albeit for a nano second put on correct way after but electrics gone crazy ignition wont switch off at all only by switching off silver key and also wipers wont switch off and starter button dosnt do anything either the red button or the black one

regards ancol

[ireland]

Doesn't sound good.

[alinton]

If it was only for a nanosecond then you might be lucky and not have damaged anything.

Disconnect the battery again, leave it off while you check all fuses including the alternator fuse ('big fuse').

After 10 mins or so reconnect battery and see what happens.

If there's still strife, pull plugs out of every control box, those in the boot, the passenger footwell and under steering wheel.

Reconnect battery. If no bad things happen, disconnect batt, connect one box, reconnect batt and see what happens. If nothing bad, disconnect batt, connect a second box, reconnect batt, see what happens!

Continue until you find a box that makes bad things happen. That box may then be faulty. Find a replacement from a friendly Cerb owener who'll lend you his, just to prove that yours is faulty.

By process of elimination you should be able to find out whats wrong.

It could also be a problem with the alarm/immobiliser - thats behind the helmet hole so temporarily disconnect that too.

Hope this helps!

A.

[victormeldrew]

I did this on my Audi, and it cost me a new alterator. Once you've traced the gremlins you'll need to make sure your battery is charging.

[Julian64]

Hmmm 186000 miles per second makes a nanosecond just under a foot, so I would say you only need to look a foot down your battery lead to find the problem.

On the other hand if you had made a mistake with the timing and we're talking 10 nanoseconds you pretty much need to check the fuses in the boot

[Duke Thrust]

Julian64 said:

Hmmm 186000 miles per second makes a nanosecond just under a foot, so I would say you only need to look a foot down your battery lead to find the problem.

On the other hand if you had made a mistake with the timing and we're talking 10 nanoseconds you pretty much need to check the fuses in the boot

lol

[GreenV8S]

Any electronics that were live are probably toast. Alternator, engine management system, alarm, radio, any other electronics that control the windows dashboard etc are all at risk. Ordinary electrical assemblies such as motors, relays, fuses etc should be OK.

[cossiemetro]

just scanned the post have you checked all the fuses fuse 10 springs to mind

[ancol]

thanks for the replies chaps ive checked the big fuse this was blown got to get a new one would the big fuse blowing probably have saved the at risk electrical components or do you think they would be shot also

[jensena]

Fuses are designed to protect things, so you may be lucky - We'll keep our fingers crossed for you.

[ancol]

have just finished checking all fuses in boot non have blown,now im about to unplug all units ,ecu ,relays etc and try and eliminate bit by bit like you say may need friendly cerb owner west mids to let me try what i thin is faulty on their car to prove which bits if any are sh@gged

[jensena]

Remeber - Nothing will work until you get the 'Big Fuse' back in. (Will it??)

[TT Tim]

Fuse here: http://cgi.ebay.co.uk/TVR-100-Amp-Mai

If you haven't already got one.

Tim

[headcase]

Big fuse is the main feed to the fuse box so not much will work without it. You will proberbly find that you have blown the rectifier in the alternator so if you put a new big fuse in it may blow straight away! If so the alternator is cream crackered, usually this ia all that you will loose on a normal car as all of the electronics are polarity protected! But is this true for TVR?

[alinton]

Don't think so, big fuse is between alternator and starter. There's a separate cable from battery to fuse box.

If the big fuse is out, everything should work except battery won't charge. Then batt voltage drops below 12v and things start not working.

A.

[ancol]

i sure hope so,anyway have found so far even with big fuse taken out some things still work ie horn,indicators,wipers heater,all lights and fuel pump well ithink its the pump when i reconnect the battery theres a noise from the boot area anyway.as the ign buttons dont do anything at all im wondering if the control box which controls those items is sh@gged im going to disconnect it in a mo and see if ign switches off then.any of you guys ever had to change some of these components and if so have you got a ball park figure on costs and where available from do you think there may be a chance of sourcing some second hand regards ancol

[whatever]

iirc, when my big fuse "went" everything else still worked ok - including un-immobilising and starting the car. Well, I didn't test everything, but you get the picture.

So,

- does the red light under the radio flash (i.e. immobilised)?
- can you un-immobilise it (i.e. red light under radio stops flashing)?
- If you then press the black button do you get the continuous "beep"? Can you hear the fuel pumps prime at that time?

If these things don't happen I'd be worried about the ecu in particular. Also, I'm not sure if there's another ignition control box somewhere.

Also:
- If you press the black button anyway, do you get any dash lights? (like battery and oil lights, the normal ones on when the ignition is)?

As for replacements... ?

[hut49]

Really sorry to see that you have such a difficult problem to diagnose and fix - you might want to make a note of Bell Hill Garage - they have second hand replacements for most things electronic: www.bellhillgarage.co.uk/tvrpartshome.htm#electronics

[ancol]

cheers chaps for the help, as i said ign lights and buzzer stay on continually and the buttons will not do anything at all to switch off ign or buzzer, also just took apart wiper control box cooked, steering wheel conrols ecu cooked,i could visually see area of toasting greenv8 was right there toasted,but on the plus side heater conrol seems fine but there again the heater did still work yesterday when i pressed button in and lit up too. also ecu dosnt have that burned smell to it that the other boxes have and looked inside no evident signs of damage so keeping figers crossed on that one,does anyone know where the door and elec window ecu are located me thinks they may be toasted also

[itsallyellow]

Im stripping out my race car and have all of the electrical boxes available. I may use a couple but not all. Send me an email if i can help.
mike