Battery terminals put on back to front... please read

adamp · Post by **adamp** » Mon Jun 09, 2008 9:14 pm

Hey guys,

Recently purchased an n12 exa turbo for a very cheap price except he had put the battery terminals on back to front... and fucked some of the wiring he said. I tested all fuses and are fine and lights, dash lights etc work but car wont start. Any ideas? He said he got the ecu repaired i didnt think it would stuff the ecu by doing this?

Please give advice

cheers, adam.

KILNIT · Post by **KILNIT** » Mon Jun 09, 2008 10:29 pm

correct me if im wrong but when you connect the battery terminals wrong, you fry the alternator

Happened to me when i got my first car

baz · Post by **baz** » Tue Jun 10, 2008 12:24 am

Wouldn't it send like a reverse charge or something?

baz · Post by **baz** » Tue Jun 10, 2008 12:33 am

Most EFI systems have a Safety Relay installed to protect the main Powertrain Control Module (PCM), the relay is wired backwards so that if someone hooks up the terminals backwards, the relay opens and cuts the PCM off preventing any damage..So basically is sends a reverse current, Radios, amplifiers and CD players are the most vulnerable. It is also possible the diodes in the alternator could be damaged..

TBON12 · Post by **TBON12** » Tue Jun 10, 2008 2:15 am

I would say the most likely scenario is the fusible links are fried, they are the 2 pink ones that come off the wire leading to the starter motor.

dexi_styles · Post by **dexi_styles** » Tue Jun 10, 2008 7:26 am

yeah or you have burnt out one wire. one wire out of a hundred... hmmm look at the wire between the dizzy n the coil..... get yourself a power/wire/ohm tester and check all wires... its a bitch but i had to do the same thing to my bros 76 corolla and found one wire was stuffed so we had to replace that wire...
good luck dude....you might need an auto electrician friend...

Post by **etking** » Tue Jun 10, 2008 11:17 am

my mate did this, fried the ECU, put another one in and off he went.

try using a replacement one to see if thats the problem or im thinking

does anything happen when you turn the key? if not im thinking fusible links (which i killed last night steam cleaning my engine bay)

adamp · Post by **adamp** » Tue Jun 10, 2008 9:58 pm

OK so i swapped the coil, and starter motor and still nothing. All i get is an oil light in the dash.. head lights n indicators n shit work. I also used an ecu from a working car.. and i know the coil and starter motor r good coz they also came from a running car. It doesnt crank at all... i couldnt see 2 pink wires coming off the wire leading to the starter motor.. can somebody please explain about the fusable links or show a pic?

baz · Post by **baz** » Wed Jun 11, 2008 12:05 am

TBON12 wrote:I would say the most likely scenario is the fusible links are fried, they are the 2 pink ones that come off the wire leading to the starter motor.

We couldn't find any pink wires..The only wires to the starter is the 1 that goes to the + of the battery terminal and the 1 that clips on the side of it and thats ORANGE..

Post by **etking** » Wed Jun 11, 2008 9:38 am

they would be going to the battery (positive) ... 2 pinky red (very descriptive) one blackish one and one purpley one ... they are your fusible links, put money on it being them .... check to see if you are getting 12v on both sides of the fusible link

the fusible link is basically 2 plugs with 4 wires going between them ... both plugs have female ends that obviously plug into mail ends on each side of it

Sabri · Post by **Sabri** » Wed Jun 11, 2008 9:56 am

as above.. etkings on the money i rekon.

adamp · Post by **adamp** » Wed Jun 11, 2008 5:50 pm

Just about to go outside and have a look! Can anyone explain why i have head lights and indicators n all that but only the oil light in the dash?

adamp · Post by **adamp** » Wed Jun 11, 2008 10:16 pm

OK so ive replaced all fuseable links with the ones off the other exa... swapped the starter motors, coils and few other bits and pieces and still nothing! HELP. Also tried 2 ecu's

KILNIT · Post by **KILNIT** » Wed Jun 11, 2008 11:05 pm

Alternator

adamp · Post by **adamp** » Wed Jun 11, 2008 11:18 pm

Yeh the alternator would cause it to not re-charge but i cant even get the car to crank...