Coolant temperature sensor wiring

[Tomtit]

Whilst manoeuvering the intake manifold I accidentally broke the two wires coming out of the coolant temperature sensor. I need to repair it but the problem is knowing which wire goes where. I have a copy of the workshop manual from U.S.A. which shows a brown wire going to terminal 1 and a red and blue one going to terminal 2. On my car I have a brown and green wire and a brown and black wire. I don't want to wire it incorrectly and possibly do more damage. If anyone has a copy of the manual for the British market and could tell me which wire goes to which terminal it would be much appreciated. I cannot start the engine until I have fixed this problem. Thank you for your help.

[Tomtit]

I have now looked at the relevant engine control module. The wires in there are clean and they are actually beige, not brown. I now know which is which. For the benefit of anyone else with the same problem, the beige and black wire goes to terminal 1 of the coolant temperature sensor connector. The beige and green wire goes to terminal 2.

[Perry Mahoney]

Glad you sorted it.  It’s always frustrating when diagrams don’t appear to represent exactly what you see in front of you.  

[Lexiguy]

Hi Richard

It's even more frustrating when you want to help but do not possess the experience, expertise and knowledge to help.

Also, as this problem would indicate, sometimes it is not easy even with the Internet and manuals at hand.

Well done, Anthony  

[Tomtit]

Perry and Anthony.

The bad news is that I have broken the electrical connector for the CTS. It has become brittle with age and heat and it fell to pieces when I was taking out the metal terminals to attach them to the wires. The engine will not run without the coolant temperature sensor correctly wired up. It generated fault code P0115. For now I have taken the terminals out of the plastic connector, soldered the wires to them and pushed them onto the CTS terminals. At least the engine will now run, and I have booked it in for the M.O.T. 

I will have to get a replacement plastic connector and do a proper repair.

[Tomtit]

I have now obtained a new connector and fixed it in place. A word of advice for anyone looking for a replacement CTS connector. The CTS has ridges along the sides which fit into corresponding grooves in the connector. The grooves are staggered - on my car the one on the left is higher than the one on the right. I could not find a part no. and did a search for the CTS connector. eBay listed many examples but for almost every one the grooves in the connector were the wrong way around. I did come across one from Brands Hatch Performance which fits perfectly. It is a replacement for Toyota part no. 90980-10736. Have a careful look at the image of the connector before you order it.

[Lexiguy]

Hi Richard

Sounds like a top tip!!!

Well it appears that you have given us many for any other brave owners out there!

Anthony