Leaderboard

Yeah, GM refers to the anti theft as VATS, Ford calls it PATS, all of my daily drivers are Fords.... I don't have any gen2 service manuals on hand but here's a basic schematic that should apply to the Regal. If you've got no voltage at the solenoid when you attempt a start you have to use your diagnostic prowess & start back tracing the circuit to find out where the problem originates. Dead at the solenoid? go backwards to the transaxle switch, if that's dead as well move on to the crank relay, where the crank relay is concerned pull the relay & test the pins for circuit continuity, probe both sides of all the contact points (in & out) everywhere trying the key in *start*. Backprobe all of the pins with your meter to test & locate where the problem lies. To me it sounds as tho you've possibly got a short to ground when you turn the key to *start*.

A security/VATS error won't shut the power down. It lights up "security light", and (in software) it prevents the starter enable relay from being enabled. My key switch was acting up, so I replaced it s number of years back.

Here's something to ponder.......is that Regal equipped with PATS?

Try doing this....it will not diagnose where the issue is but.... with the ign key on in run position, using a simple screwdriver or one of the ends of your booster cables with the jaws open, bridge the large battery terminal & the small solenoid terminal of the starter, do NOT go to ground anywhere, will the starter crank & the engine fire?

Fwiw, this is likely easy to find. But, it will take a little time/effort. However, also, there is a slight chance that a main wire/connector has corroded through. Note, I said slight. This could be done very quickly with 2 people. It takes longer with one person. Here is what you must check (or, check things randomly, and hope for the best :)) 1) Put the DVM probes directly on the battery terminals Turn car to start, note any voltage changes. 2) Put the one DVM probes directly on the battery POS terminal, put the other on a good solid engine ground. Turn car to start, note any voltage changes. 3) Put the one DVM probes directly on the battery POS terminal, put the other on a good solid body ground. Turn car to start, note any voltage changes. 4) Put the one DVM probes directly on the battery NEG terminal, put the other on the POS battery cable. Turn car to start, note any voltage changes. 5) Put the one DVM probes directly on the battery NEG terminal, put the other on fuse for the cigarette lighter. (this is not a switched fuse, it may eliminate the ignition switch). Turn car to start, note any voltage changes. You will then move to the ignition switch connector, or elsewhere. Try to find an ignition switch diagram for your model and year online. That will help a lot. Fwiw, I've had three cars that have had main power wires go bad. There's a youtube video that shows a similar thing on an early 2000's Mercedes. So, I guess it has become more common, with the use of cheaper (but still better than average) wires. However, ~99.99% of the time, it's a bad/poor connection, or bad wire over all (such as it's falling apart). Good Luck!

Do you have power to the bigass cable at the starter solenoid? Should have battery voltage. When the starter cranks, the voltage at the battery will drop. No matter what, that cable should have battery voltage. Do you have power to the purple wire attached to the starter solenoid "S" terminal when the key is turned to "Start"? No power on the purple wire with the key turned to "Start", no starter cranking. Did you ever check the fuses?

I agree with the above, also double check everything you touched when replacing the battery and motor mounts. Loose or missed connections, pinched wires, etc.

It seems like you have power, and then when you go to crank you have nothing. I've dealt with that issues before as I have let my cars sit for long periods of time. It's typically a low battery, or a wiring issue (ground wire, wire to starter, or something like that). Corrosion sucks. Dielectric grease on your wiring connections makes a big difference.

If the lights are going out and the gauges go to zero while trying to crank that sounds like an electrical issues to me. I would check the battery connections. Especially the ground. Check to see how many volts the battery has. A healthy battery should be around ~12.6 volts. The engine light will be on until the vehicle starts unless there are codes then it will remain lit.