Ever since I picked up this jeep two months ago the blinkers have been slow, especially with the running lights and AC on. When trailer lights are hooked up too. Any ideas on what could be causing this?

 

Other things aside, the speed of the blinker is a "poor man's volt meter". I'd start with metering voltage right at the battery. Around 14 is nice, running. Last I checked I idle at 14.25 with everything on.

 

If they slow down when you turn on the headlights and blower, it could be the belt.

 

How can that be? There's only one belt. You are going to hear it squall if it slips. The flashers will definitely slow down when you put a bigger load on the system.

Voltage is controlled by the PCM. It doesn't matter if you have a 340 volt alternator, it's only going to let a certain amount of amps through.

He should change out the flasher for a quality heavy-duty version. It might help. Or it might be that is just the way his Jeep is.

 

OP's is internal regulator, but I would do as you say and replace the flasher with a HD unit. Perhaps cables and grounds are not up to snuff also.

OP: Ever refreshed the connector in fromt of the air cleaner that has all the wires for your front lamps?

 

I have not, I will try that

 

If one had a 340 volt alternator, wouldn't that make the dude on the radio sound like an auctioneer? I think the wipers would also melt the windshield, just sayin....

 

LOL. The point I was was trying to make is that the PCM is like a valve or dam, in that it will only let a certain amount of amps through from the alt to the system.

I'm sure someone will correct me on this, but I think 14.2 amps are about it.

 

14.2 VOLTS. Amps are what aren't regulated. Could just be that the PO replaced the factory 100+amp alt with a 70-90amp one.

 

I understood. Alternators just "maintain" a charge anyway. The battery stores it. It gets to the vehicle's accessories by nice and clean connections.

 

I can't believe nobody has suggested a lighter weight blinker fluid yet. I am disappoint.

+1 to all of the above. The old mechanical flashers react very strongly to resistance in the circuit path, hence why you lose a bulb or install LEDs and it blinks super-quick. I'd be suspicious of marginal grounds and/or a corroded connector that's presenting high resistance. Check the connectors mentioned, as well as grounding points by all of the light fixtures.

 

I've looked everywhere, no-one around here stocks the HD blinker fluid.

 

Try and find the amber colored fluid. Easier to find than the red.

 

Wherever you regulator happens to be it will try to keep the voltage up. If my voltage was not up, the belt is the first thing I'd check. The belt will not always sequel. Radi had an excellent tip. If voltage is reading low under load, turn it off and feel the alternator pulley. If it's unusually hot, it was slipping. The voltage test, and that can be done in two minutes. Then move on to other tests. OP, the alternator output goes right to the big terminal on your starter relay, pictured in the link in my signature.

 

Ok, I just went out and tested a bunch of stuff. Battery voltage: 12.77v Alternator output: 14.1v. I turned everything on for the voltage tests. The dash volt meter reads 10-11v. I took a video of my blinkers working. The side markers blink... My 89 didn't do that, it was just the two under the headlights that blinked.when the lights are off no problem. Lights on, the side marker and turn signal alternate. What is this?