Tach works fine untill lights are turned on then it cuts off

I need a VSS which i ordered, Would this be the culprit still? Doesnt seem like it should, seems like it has something to do with the lights but idk.

 

My quick answer is that your tach is somehow grounding through your lights(parking lights?) and missing a ground of it's own. Are we talking about the stock tach or aftermarket?

 

Stock, tach i just got the car and the wiring for the bumper lights were a mess i tapped them up to keep them from grounding but half of them dont have the plugs or sockets that are suppose to come with it.

 

The answer is right in front of your face

 

check to see if your alternator is sending enough amps thru out your electrical system... i had the same problem and it turns out my alternator was shot...turn your car own during the daytime, check if the tach is working if it is...push the brake pedal down, does the tach suddenly drop down?

 

I had alt tested today they said it was charging good, I charged battery up over night and decided to take it in with alternator it tested good. But i notice my HID's come on when cars off, but not when cars on, Is my battery bad?

And as for you AcidCrakker, If your not going to post something the least bit useful, then go play with yourself on some other topic, and stop spamming up my thread.