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Wiring help after TT auto to manual conversion + ABS removal


David Reid
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Before I get to the problem my car is a J spec TT manual shell and body loom, with a UK TT auto engine and loom, but with a UK TT manual ECU and getrag 6 speed.

 

I have joined the black and black and white wires described by dude in his auto to manual conversion thread to try and overcome the neutral crank lockout.

 

I have also removed the ABS and gearbox ECU as this is a track car (I think this is the problem).

 

The car is converted to single (maf still kept) and I appreciate I will need to get it mapped on a standalone ECU, I just want it to run as is, in order to move it arround and get it closer to being finished.

 

Now the problem, after re-assembly everything is normal at ignition on, i.e dash lights heater control work, fuel pump runs. But when I go to crank nothing (i.e engine does not turn no solenoid click nothing).

 

I have checked the back of the ignition barrel and there is a switched crank feed out (black with white), this then dissapears into the fuse box by the drivers feet. The crank fuse is OK and live when cranking this then dissapears somewhere (yet to find).

 

Checking at the starter 0v when cranking, so something in between is the problem.

 

Can anyone help?

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ok so when you try and start the car and hold the key over as if keeping the starter going the black - white wire is positive, reason i say this as im doing a 1jz conversion and found this wire as a positive when trying to start the car, if you put the ingition lights on and give that black - white wire 12v it should start the car, althought if you havent done the Negative as if the car is in Neutral then it may not supply a 12v to this wire in the fuse box.

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ok so when you try and start the car and hold the key over as if keeping the starter going the black - white wire is positive, reason i say this as im doing a 1jz conversion and found this wire as a positive when trying to start the car, if you put the ingition lights on and give that black - white wire 12v it should start the car, althought if you havent done the Negative as if the car is in Neutral then it may not supply a 12v to this wire in the fuse box.

 

Yes black with white is positve when trying to crank.

 

Sorry I dont understand the next part of your reply, the black with white wire already has +12v, so appling +12v will make no difference.

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What do you mean by gearbox ecu dude????

 

I was really hoping you would read this :)

 

I stripped the ECU's out when I installed my cage (18 months ago)so excuse me if it not very clear.

 

I am assuming the auto used a seperate gearbox controller (i.e not integrated into the ECU). I must have removed this and have since thrown it away :(

 

I also have several plugs where the ABS used to be that are unused. Where does the gear ECU normally live I can then check if I have a crank feed in any unused connectors near it?

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The gearbox control on an auto is taken care of by the main ecu, you must have removed the TRAC ecu but you say you have removed 2!!!!! If you have joined the wires together the starter should engage.

 

OK, maybe ABS + Traction?

 

I joined these two (from your thread), the blue arrowed ones, you cant get them wrong as they are the only two raised ones in the connector.

 

attachment.php?attachmentid=99895&d=1255542288

 

To confirm the crank signal path to the starter my undertsanding is as follows:-

 

Ignition barrell

to

Fuse box in drivers footwell

to

Wiring over dashbar and down passenger side a piller

to

Connector block in passenger footwell

to

park neutral switch

to

ECU

to

starter?

 

I have not tried checking for start signal at the park neutral switch (soldered together above). I will try that tonight

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Hi David

 

When turning the key to start position the ST1 output on the Ignition barrel sends 12v down a black and white wire firstly to the fuse ST... Then the other side of this fuse the wire turn to the colour black until it reaches Connector IJ2 where it turns black and White again. This wire then if your loom used to be an Auto then goes to the Park/Neutral Postion Start Switch. If you have bypassed this you should have joined the black and white wire together with the black wire.

 

Firstly check if you are getting 12v on the black wire if you have bypassed the P/N Start SW when turning the key to start.

 

You should have and if so this black wire then runs to the engine bay fuse box to the Starter relay.

 

My bet on the problem is that the negative side of the coil of the starter relay is not grounded as this normally goes through an Alarm system and commonly overlooked on conversions.

 

If so pull the fuse box apart and on the underneith of the starter relay join the white/back wire to another ground source (check with meter)

 

Then you should be away

 

Make sure you have a ground Earth from the chassis to the engine also ;)

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You have changed the wiring under the fuse box for the NA/TT conversion havent you???

 

No not changed anything arounfd the fuse box (engine bay I assume).

 

Neither my body loom or engine loom is NA, both are orignal TT, but one auto the other manual, so I assume I dont need to change am I correct?

 

Maybe no one before has tried TT Auto engine loom to TT manual body loom.

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Hi David

 

When turning the key to start position the ST1 output on the Ignition barrel sends 12v down a black and white wire firstly to the fuse ST... Then the other side of this fuse the wire turn to the colour black until it reaches Connector IJ2 where it turns black and White again. This wire then if your loom used to be an Auto then goes to the Park/Neutral Postion Start Switch. If you have bypassed this you should have joined the black and white wire together with the black wire.

 

Firstly check if you are getting 12v on the black wire if you have bypassed the P/N Start SW when turning the key to start.

 

You should have and if so this black wire then runs to the engine bay fuse box to the Starter relay.

 

My bet on the problem is that the negative side of the coil of the starter relay is not grounded as this normally goes through an Alarm system and commonly overlooked on conversions.

 

If so pull the fuse box apart and on the underneith of the starter relay join the white/back wire to another ground source (check with meter)

 

Then you should be away

 

Make sure you have a ground Earth from the chassis to the engine also ;)

 

 

Thankyou, I will investigate when i get home with some day light

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