The V8 Owners Forum -

Hello folks,

I'm using the throttle body off a P38 inlet manifold which has the TPS already attached but I don't know which connection is which. If I remember rightly it's like this:
http://www.brit-car.co.uk/product.php?xProd=99029

Anyone know the wiring and/or does anyone happen to have a plug and wiring 'tail' that I could have? It doesn't seem to be a standard fitment.

thanks
Mike

You can infer the wiring pretty easily. The resistance between two of the connections will remain constant irrespective of TPS position. The other one is the wiper, which will change it's resistance between it and the other two as you move the shaft.

Chris.

Thanks Chris, I'll have to dig out the multimeter then - and find the instructions!

Mike

Dont think you'll do any damage with incorrect wiring.

But you can wire it up wrong. If the wiring is reversed it will read Lo-Hi, or Hi-Lo

So you'd need to know which way the signal needs to go as the throttle is opened.

stevieturbo wrote:Dont think you'll do any damage with incorrect wiring.

You can do damage if you have the wiper connection in the wrong place. This is because at one end of the scale, the wiper is directly connected to that end of the potentiometer. In other words, two of the pins are a dead short. If you have those two pins connected to 0V and +5V (or whatever the supply across the TPS is), it may destroy the TPS. However, the driving circuit may allow for such a mis-wire, and protect the TPS.

Chris.

Pretty sure I found the right connector:
http://www.simtekuk.co.uk/www.simtekuk. ... h=&sought=

Also pretty sure I've got the connections sussed. Between 2 of the pins the resistance goes from 1.06 to 2.71 k. Nominal resistance on the tps it supposed to be 2.5k but that's with 20% tolerance - which sounds a lot. I just need to update my MS with the current values and it's another job done.

Mike