Solution to random electrical issues on '02 GP?

[NotEnoughGPs]

In the past few days, I have been experiencing more and more electrical issues with my 40th Anniversary GP. It has 202,000 miles. I installed HID Spyder headlights in 2007, with the upgraded wiring harness. There has not been any other mods done to the car involving the electronics.
The battery is a Optima red top, manufacture date May, 2013
The original alternator crapped out back in December of last year. The new one has been working fine. The charging system light has not come on.

Here are the issues I have been seeing recently:
- the horn will sound one time for like 2 seconds, then it will stop. This is a very rare occurrence, happens about 2 times a year. Most recently, it went off last week for a few seconds, then stopped.
- A few times I noticed the high beams would not work. All other exterior and interior lights worked as usual. I checked all connections and could not find anything wrong. I kept trying the high beam switch to no avail. Then, the next time I drove, the high beams worked normally.
- A few days ago, I noticed the DIC went off, and the gauges stopped working, and the power door locks activated. Then, after a few seconds, they started working again. This happened just one time. Then, last night, same thing happened with the DIC and gauges and power door locks, and the heater and radio went off, but this time, the SRS air bag light came on and stayed on. Then, after a few seconds, everything worked properly.

I have done searches for these issues and looks like the problem could be a bad ignition switch.
Also, I have checked the battery cables for proper connections and all is well. I checked the grounds and all are tight and clean.
Also checked the main wire going to the alternator and it is tight.
I have not had either of these tested. I don't believe there is anything wrong with them.

On top of all this, the tensioner pulley bearings have been making noise, and yesterday, it got really noisy. I am putting on a new pulley in a few hours.

But, concerning the electrical problems that I stated, do you believe it is the ignition switch?
Today, I need to replace the tensioner pulley. Then I have to drive the car about 50 miles.
In your experience, if it is the ignition switch, is there a chance the car will shut down completely?
If so, what could I do with the ignition switch to get the car running again?
And last, where can I purchase a new switch?

Thanks for reading:th_thumbsup-wink:

 

[BillBoost37]

Check the wires that go to the front most trans bolt. Those ground the majority of the car. If the wires are nearly broken you will have intermittent ground issues.

 

[NotEnoughGPs]

BillBoost37, I located the transmission housing bolt that is most front. To verify, just to the right of this front bolt (about 2 inches or so) there are 2 transmission fluid lines that are routed.
This trans bolt is located above the engine starter.

On this trans bolt, I see a black wire (I believe that is the ground wire from the battery) connected to this bolt, and also 2 smaller wires.
All these wire are intact. There are not bad in any way. I have never done any work in that area.
It is also dry in the area around that trans bolt. The rest of the trans is damp from engine coolant from the LIM gasket leak.

Just in case there is corrosion on this trans bolt with the wires that I cannot see, do you think it is worth removing the bolt?

I will be driving the car in next 15 minutes. I will report back if the random electric issues continue.

 

[BillBoost37]

Those two small wires were the ones I suspected.

When's the last time you pulled your battery cables and looked to see if there's corrosion there?

 

[Bronco Boy]

In your experience, if it is the ignition switch, is there a chance the car will shut down completely?
If so, what could I do with the ignition switch to get the car running again?
And last, where can I purchase a new switch?

I think Bill has you on the right track, but in regards to the ignition switch.......

From what I know of them, the car won't shut down completely. When the switch is bad, it effect "accessories", like auto lights and the blower motor. The car will still run and operate, and typically the switch will eventually engage and all your "accessories" will work. The switch can be had on e-bay, look for AC Delco. I think I paid about $75 for mine early last year.

 

[NotEnoughGPs]

Because I had the DIC, gauges, radio, heater fan go out on me briefly on Monday, I wanted to check the battery and battery cables for corrosion. There was none as I make a regular check of this due to fact I drive the car so much. I use dielectric on the connections and have never seen any corrosion.

I did install a new tensioner pulley this morning. Half the bearings were gone in the old pulley. Funny that as the pulley started to shake and vibrate more and more this morning, that was when the DIC, gauges, radio, heater fan, and door locks cycled. And the SRS Air bag light came on and stayed on for about 30 seconds. Then everything reverted back to normal.
Maybe the pulley had an effect on the alternator?

Just got back from driving the car about 50 miles and did not have any issues.
I did move around the ground wires connected to the trans bolt, checking for tightness.
I am going to take the time to remove the wires at the transmission bolt to make darn sure they are clean.

I know Bill is steering me in right direction. With the miles on this car, and the relatively few problems I have had in 11 years of ownership, I don't doubt that the ignition switch has gone bad.
I will look into the switch bypass procedure described here on the forum.
If I can't make that work, I will get a new ignition switch.

Thanks Bill and Bronco Boy