Hi, I've been having a problem with my F150 lately that is extremely annoying.
The radio will shut off and turn back on when I do just about anything it seems. Turning on the headlights, shifting into gear, hitting the brake pedal, letting off of the accelerator, hitting the turn signals (will shut off/on in sync with the turn signal delay), etc.
I just put in a new 140 AMP Powermaster alternator w/internal regulator. It was cutting on/off prior to the new alt. but not as frequent (I thought the new alternator would actually be the fix to this since the old one was on its way out). Now it seems to be getting worse with the new alt. doing it just about everytime I do one of the above mentioned things. Will do it whether the headunit is on radio, cd in headunit, or cd in 10 disc changer.

I was thinking maybe a bad ground wire somewhere getting looser and looser? But it will do it even at a stand still with the engine off now, so does that rule a ground wire out?

Now I am thinking it might be the voltage regulator? I don't know what else it hooks up to now that the wires from the previous alternator are disconnected from there since the new one didn't need them... but I don't know where the regulator itself is to just take the whole dang thing out since it is no longer needed. Could this be screwing with me causing the radio to do what its doing even though it is disconnected from an alternator but still connected to whatever else?


Really would like to get this figured out as soon as possible... really irritating when you can't even listen to a full song without the radio cutting on/off 50 times.


Oh by the way----- engine is a 351w.

 

If you are asking where the voltage regulator is, it's inside the altenator.

 

It looks as though the stock one was external though. I can't really follow the two wires that where hooked up to the old alternator and am not really sure what the regulator looks like in the first place. The new alternator however, I know it is an internal regulator.

Even though the old external stock regulator is not connected to an alternator (the new one that has an internal regulator), could that still be playing a factor in what I am going through? Regardless, I would like to completely disconnect the stock now-useless external regulator just to know.

 

Pre-'87 VRs are on the R inner fender, near the battery. But it's a GOOD & easy upgrade to swap the whole mess for a later stock Ford 130A 3G alternator. Go to FSB & read one of the big 3G Swap threads. You can buy everything you need from FireGuy50 (Ryan) or use the info on his sites to get what you need from the junkyards.

 

I just recently bought the Powermaster 140Amp one wire, internal regulator, alternator for 100 something, so not really looking to go and buy another alternator lol. The alternator works great. 140 was probably overkill since my truck doesn't have much that would be drawing off of it, but it fixed my headlight dimming problem and now I can finally run the KCs and headlights at the same time with no problems.

All I really want to do is fix the damn radio problem but I don't know what is causing it. I was thinking that maybe if the stock external regulator is still attached to the wiring harness but no alternator, it might be reading screwy since theres no power going into it? Not sure if that makes any sense but I don't know much about how the voltage regulator works. I know the previous owner who I talk to a lot and knows the truck very well said the radio was always really sensitive to voltage drops. He said it would cut the radio off then on when he would operate the plow system that was on the truck.

 

That sounds more like bad grounds than anything to do with the alt or VR. I doubt the old VR would have any effect on anything anyway. If it did, it'd be blowing fuses. If it's there, unplug it.

If the radio is the problem, diagnose IT - not the alt or VR. If your diagnosis LEADS you to the alt/VR, then you can address them. Find out if the radio is losing power or ground when it dies.

 

Earlier today I found the old voltage regulator. I only had a few minutes before work to screw around with it though.
I tried to disconnect the connector going into it, but space was cramped due to other wires in the way. I got it about halfway off because I couldn't get the lower-most part of the connector to pull out because the tab was still holding it.
So half of the connection was out anyway... and I had to leave for work.
It seems that it stopped the problem so far. However, I think the connection might have popped back in because it was doing it a little again on the ride home.
I'll have to get it fully disconnected before I can really know if that was at fault at all and if it remedies the problem.

Thanks for the help everyone, I do really appreciate it.