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2014 Chevrolet Sonic - Short!

2014 Chev Sonic LT / 84,000 miles
When driving, the Traction Control Light, Battery lights come on, then you can steer it. Turn car off and it wont turn over, so have to let it sit for about 10-15 minutes then it will start. The battery light stays on for about a day
I’ve had the battery replaced, which it didnt need, I’ve had several diagnostics done and everything checks out fine, the last computer check indicated "Communication codes check found loose ground in engine compartment, tightened ground… The very next day it’s happening again, at wits end … I did notice today as soon as I turned on the AC it happened again.I dont know what to do, this unreliable and unsafe…Please help anyone, suggestions, experiences, etc… Thankyou

Check all ground wire’s there are more than one.

I’m taking my car in tomorrow again, so I’ll tell them to check all ground wires… Do you happen to know how many there are… Any thing else they should check? I really appreciate your help…

l am disabled and this car is just not reliable and its costing too much money trouble shooting…It seems the mechanic’s really dont know what to do next.

I’ve taken it to 2 Chevy Dealerships…

Again thank you so much for your help…

Have no idea how many ground’s on your car but a good mechanic should know.As far of what else to check tell the mechanic what you told us

It sounds like the various special purpose computers (there may be several) in the car may not be able to reliably talk to each other. When that happens it’s like how a telephone on the blink affects your work output. Sometimes you can get stuff done (when the phone is working), and sometimes you can’t (when it isn’t). There’s probably test procedures using the chevy scan tool to test all those communications paths. But that procedure is likely fairly complex, and something a computer scientist would be more likely to be able to do than a shop mechanic.

Two options

  • find an electrical system auto mechanic who specializes in this sort of computer to computer diagnostic work .
  • take a guess a grounding problem still remains and do what’s required so all the ground connections that can be found in the engine compartment and passenger compartment are clean metal to clean metal and tight.

Other ideas

  • There’s inexpensive test gadgets you can buy that purport to make finding short circuits easier.
  • Do this simple voltage test and report back what you measure. Before first start of the day the battery should measure about 12.6 volts. Immediately after starting the engine, 13.5-15.5 volts.
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I would use a well recommended (online reviews, friends, and family, etc) independent mechanic instead of a dealership once the car is out of warranty. In addition to the ground wires I would also check and make sure the negative battery cable is still good as well, they can corrode over time internally

I am NOT familiar with the Sonic at all so my comment is on meant in a general sense. Many GM products (and SAAB also) use a terminal junction. This is usually located near the battery positive terminal. Just follow the lead from the positive battery post to what may be a small black cover. With the cover open you would see several heavy gauge wire leads.

Over time the lead ends will develop corrosion or scale on them. This can cause failure to start, intermittent dying, and so on. Just some food for thought. Hope it helps.

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