Occasionally, blinkers go crazy - erratic flashing - when I crank up? Faulty relay?

The most common cause of a non-starting car is the battery. It is either weak, (low voltage) dead, (zero voltage) or has bad connections. (corroded or loose) I will assume you have a fully charged battery with good connections. (both to battery and starter relay)
If you remove the starter switch lead (small wire) from the starter relay and apply +12v from the battery to its respective prong or lead on the relay, and your starter cranks, your starter switch is faulty. (not to be confused with your key switch). If you jump the two large wires together on the relay and it cranks, then the relay is faulty. If you jump the two large wires together and nothing happens, then starter is faulty, or wires to starter are loose or broken. Picture of starter switch prong on the relay is pictured. NOTE: sparks are to be expected, so don't be too scared. Pictured is a starter relay that is seperate of the starter, on models with starter and relay mounted together, its very similar.


If you car has an immoboliser system, it may be faulty.

there's the location of unit flasher. But for what I seen you could have a rear end ground problem. have a look hope it helps

I believe this is still an old fashioned bi-metal flasher system.the flasher has two metal strips bonded together that expand and contract at different rates,causing the strip to bend.This causes the strip to bend,turning the circuit off.When the strip cools,the strip straightens out and turns the circuit on(this happens repeatedly to flash the bulbs).Because cool tempuratures make it work better,I think the flasher is bad.

Sounds like you have a faulty signal switch.

Sounds like the blinker relay is bad and needs to be replaced. If the lights actually work, even though occasionally then the relay is bad.

Usually when this happens it is due to a relay in your fuse box failing. There are 1 or 2 relays which turns the constant flow of electricity to your lights to intermittent when you use your blinkers. If the light is constant when you use your blinkers the solution will be to replace the faulty relay.

Had the same problem. There was something loose under the fuse box on the drivers side under the hood, If I moved it, the lights on the i/p and drl lights came on and it would start

you need to go back over all the bulbs. Take each one out and put it back in making sure its working properly. Most likely a bulb is not grounding. I had this on a f-150 that took two days to track down. Good luck

check to see if the power steering pump is binding do you have the defroster on when this happens? if so it maybe the a/c compressor turn the defroster off and try to start it .

Ignition switch, maybe?