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Q: My 2009 Cadillac CTS won't start

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2009 cadillac cts 3.6. Problem I'm having is I can't start the car, or even get a click. My battery is good, lights are on. Dash on, signals work. When I checked the starter relay socket I have very low voltage. I can jump the car with wires going from starter relay socket into ground. I think something shorted out. I checked the wires to fuse box, all are good nothing frayed or burnt. When I put my test light in the socket I get a clicking sound near the engine, I can't see where it's comming from but it sounds like it's in the housing right on left side of intake manifold where the big hose goes into the intake. Trying to take the cover off its hard and im scared of making this worse. So my question is really why do I have low current in the starter relay socket. The relay is good. I changed it anyway. Can you guide me? Thank you.

My car has 60000 miles.
My car has an automatic transmission.

A: I’m a bit concerned about your description ...

I’m a bit concerned about your description of using a jumper wire to ground at the starter relay. Either you can make the starter motor turn from here, which you could if you jumper the correct terminals with power, or you used a jumper wire and something shorted out. Which one of these is the case is not exactly clear. If you did short something out, this becomes more complicated.

Your Cadillac relies on the ECM (engine control module) and the BCM (body control module) to start your car. For this reason, you will need a scanner that can access data from your car. These modules communicate via data lines that only a computer can make sense of. Also, there are four separate wires going into the starter relay. Each one needs to be treated differently and this can only be determined with a wiring diagram. If you don’t have access to these two items, I recommend having a certified technician inspect the starting problem in person in order to get this properly diagnosed and repaired.

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