garys 68

iTrader: (1)

I just installed the harness and computer for a 2002 Escalade LQ9. I got a 118 code ( engine coolant temp hi) when I turned the key on.
The circuit with yellow wire on the coolant sensor was good to the pin 74 on the computer. However the grey wire on the coolant temp sensor was cut. The diagram shows this is supposed to be connected to pin 41 of the computer. There'a also no pin in the computer connector for pin 41, I assume it was removed by the guy who did my harness.
This terminal is labeled as ground on the computer and also grounds the automatic transmission TFT sensor (I'm not using the auto trans, I've got a Richmond 6 speed instead).So my question is do I need to run a ground from the grey wire on the temp sensor to pin 41 of the computer, or will an engine block ground work?

Ryco88

Grey wire from the temp sensor has to be hooked into pin 41 of the pcm. This is the low reference for the temp sensor. Pcm won't be able to tell the sensor temperature without this wire hooked up.

G-Body

iTrader: (4)

Yep, just run the ground all the way back to the PCM, you will kick yourself later if you don`t. The PCM`s are very sensitive to grounding of sensors, if you ground it to the engine you might end up with intermittent codes of the PCM thinking the temp is off.

garys 68

iTrader: (1)

Anyone have an idea where I can get some pin connectors for the strip that plugs into the computer?

LS1MCSS

iTrader: (18)

How many do you want? I have a bunch of slightly used ones, from harness mods. You can solder and heat shrink your wires to them.

Ryco88

Check pin 63 of the same connector. Some modules used this pin for the low reference on the temp sensor if there is a grey wire there than that would be o.k. to use.

garys 68

iTrader: (1)

The guy who reworked my harness finally called back. He's sending me some pins. Thanks for the help everyone.