Hey guys. I recently acquired a '97 Bonneville which had a lower engine knock. Along with the car came a engine with half the miles on it and the guy (good friend) had tested it before he removed it from the other car, same year and make.

After a week of on and off work, I got the engine out, new one back in and everything hooked up. To my surprise it actually worked lol. So far no mechanical issues what so ever and it sounds great.

My issue is that after starting the car the turn signals will flash and you can hear them clicking, they wont flash on the dash just the bulbs outside. The dash lights (just illumination, no idiot lights come one) and up until i replaced the factory radio with an after market the radio would flash with the signals.

This hasnt prevented it from starting or running, and it stops after few minutes usually 2-4. it usually wont do it again unless you shut down and restart. Also today i noticed that the interior lights were on while driving, and sometimes flash off then on. I checked the switch and of course they were not on.

Im a bit at a loss here with this one, im pretty mechanically and electronically inclined and havent been able to find a reason for it. The previous owner did say he thought that it would happen if the car was locked with the FOB and then not unlocked with it but with a key. Of course he cant find the FOB and not sure where to find the model number of the original to get a replacement.

I know this was a bit long winded but anyone have any ideas??

One other thing I did leave the original computer in the car so as not to interfere with the VATS, only thing I did change out was the wiring harness with the one on the new engine.

Kinda confused here, but did the lights start doing this AFTER you installed the new radio?

Nope, started the first time i started the engine. The factory radio was wired into the dimmer in the car, which is why i think it was flashing when the dash and signals did. The new radio doesnt connect into that circuit, it controls its own lighting.

Re-reading that first post i see its a bit confusing. let me sum it up. start the car signals and dash lights flash in sync. goes on for 2-4 min. started before radio switch.

That'* really odd but I don't think it has anything to do with the engine swap. Can you unplug the harness for the light switch and see if the problem goes away?

I agree, I have done engine swaps etc on 95'* and 97 and have not experienced this either.

Did you by any chance remove any of the front lights while doing the engine swap? If so, I would check all the wiring for possible pinch points resulting in short to ground.

Ill be checking the wiring today for any possible shorts. What he said about the locking it with the FOB and not unlocking it with it, does that sound feasible? Could it be something with the security system?

Is there any way to reset it back to default settings?

And thanks guy I appreciate the help.

VATS has nothing to do with lights or door locks. It'* only designed to prevent the engine from starting. On the 96 and up, the VATS does not allow the fuel pump to prime. On 95'*, it prevents the starter to engage.

But first, we need to eliminate the possiblity of a short in the front lighting system. Check every single circuit in the engine bay and front area.

OK Ive checked all the wiring that i can get to and is see no pinches, bare wires or any where that i could have a short. Now that doesn't take into account anything in the dash or firewall.

To keep the battery from draining as now the dome lights are staying on all the time I pulled the fuse, still have the flashing signals and dash-lights. The thing that strikes me as odd is it does it at start but will stop after starting to drive. If it was a short i would think that it would happen more randomly and not stop so predictably.

There are only two grounds on the 96-99 engines that should have come into play.

Main battery cable to front of engine block between starter and AC compressor. Sensor ground on back of block (passengerside) next to oil filter adapter/pressure sensor.

I would check both of those for any corrosion for looseness, and check both battery cables as well for corrosion. After that I'd be hitting the ground busses at the door sills.