Where's the main ground cable for 1990 Accord LX located? Is it that short thick cable that goes from the negative of the battery to the side fender?

Thanks.

 

It is bolted to the tranny housing if you follow it from the negative terminal down. There's also one at the Intake Mani too which will be a ground wire harness for the ECU.

 

So if it's bad, it could cause my battery light to go on? How to test it to see if it's causing the light to go on?

Thanks.

 

It will not be a ground problem if you have a battery light on. It's your Alternator that isn't producing voltage to keep the battery charged. A ground issue will cause the whole dash including your gauge cluster to black out when you crank the key all the way to fire up the engine.

You'll need a VAT-40 to test out the Alternator if you know what you're doing then you'll get the right results.