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Q: No power on purple wire in start position....new starter..runs if i jump relay

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every thing is working....except no ground signal at terminal #30 on starter relay when key is turned...if i jump relay starts and runs fine.....i have replaced starter...ignition switch.....neutral safety switch...and relay

My car has 170000 miles.
My car has an automatic transmission.

Hello. If there is no ground getting to the starter relay then the computer is not energizing it. Typically when this occurs it is due to the computer not receiving a signal from the ignition switch or from the transmission position sensor. It may also be the computer itself.

The way to know for sure is to use a computer scan tool that can see all of the powertrain control module data. I usually monitor it to see if it is getting these signals. If it is missing any of them then that circuit needs to be diagnosed. If it is and does not energize the relay then the computer is bad.

If you need help with getting this fixed, consider YourMechanic, as a certified mechanic can come to your home or office to perform these checks and properly diagnose your electrical issue.

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