I did a m6 to a4 swap on a 98 i changed the engine harness out now my temp gauge isnt working i have 5 volts on the yellow wire ive checked it with a meter im not getting any ohms on the black wire back at the pcm i tried running two new wires to the pcm to bypass the harness same thing gauge is dead it has a new pigtail and sensor im not getting 12 volts on my green gauge wire ive checked all the grounds is there a way to run a new wire to the gauge im thinking i may have a cut wire somewhere in the harness ive taken off all the wire loom and i cant seem to find any issues ive looked at the wiring diagrams on the temp gauge but i cant understand how to jump a wire to the sensor to the gauge i noticed all the gauges share the same power which makes me think i could have a possible grounding issue but i cant find it sorry if this sounds confusing

 

[QUOTE=hakko98;17641308]I did a m6 to a4 swap on a 98 i changed the engine harness out now my temp gauge isnt working i have 5 volts on the yellow wire ive checked it with a meter im not getting any ohms on the black wire back at the pcm i tried running two new wires to the pcm to bypass the harness same thing gauge is dead it has a new pigtail and sensor im not getting 12 volts on my green gauge wire ive checked all the grounds is there a way to run a new wire to the gauge im thinking i may have a cut wire somewhere in the harness ive taken off all the wire loom and i cant seem to find any issues ive looked at the wiring diagrams on the temp gauge but i cant understand how to jump a wire to the sensor to the gauge i noticed all the gauges share the same power which makes me think i could have a possible grounding issue but i cant find it sorry if this sounds confusing [/QUOTE

so the wire to my gauge is bad i cant track it down all i need to know is if i can supply a new wire with 12 volts to the gauge and ground it without messing up something im guessing having a short on the green wire is causing the pcm not to see the temp??

 

Ok so i traced the wire that sends signal to the gauge on the three wire plug for the temp sensor it splits and goes to the Throttle position sensor signal pin 12 on the blue plug on the pcm the other wire goes to in line connector c100 and there isnt a wire on the other side of the plug so i dont know what type of signal i need to hook to it if i need a 5v reference or what

 

yeahhhhh so im an idiot the tps plug is identical to the temp sensor plug on the 98s had them crossed

 

I did the same thing. lol Car kept giving me a tps code and a coolant temp code. Turned out I had the plugs swaped.