I put a set of LED bulbs in an 08 for a friend of mine last night and of course it was hyper flashing. I had hoped we could fix it by reflashing the bcm, but we couldn't find a calibration or option in TIS2Web to take care of it. I built some resistor packs last night to simulate the load of the 3157 bulbs, and it worked perfect all night. This morning he called me and said it started hyper flashing again. He brought it back over, and I redid some of the connections. Once I got it all back together they were working right again, but he called me not even five minutes after he left and said it was doing it again. Anyone else ever had this happen or have any idea what is going on?
LMM turn signal hyper flash with LED bulbs
- Thread starter JoshH
- Start date
Couldn't tell you what's happening there but I installed this on my truck- http://www.amazon.com/Novita-LM487-Flasher/dp/B001KS6GIG
That won't work on an LMM. Unless the research I've done is wrong, LMMs don't have a flasher module; the turn signals are controlled by the BCM.
That's what I was finding on the internet. I can't do that though because I'm not a dealership and don't have the dealer code to give them.
Have him take it to the shop of a dealer and give a mechanic $5 and he'll probably do it
Also interested mine does same thing after doing switch backs should I just wire resistors or get bcm flashed and how would I got about getting bcm flashed just tell dealer I put LEDs in
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I wonder if your resistors are getting hot? The resistors I got with my LED bulbs have ceramic heatsinks built in and they get HOT in a hurry.
As intermittent as it is, I don't think so. The first time it acted up was as soon as he started the truck to leave the driveway. The next time was after he had been driving.
Someone has posted the module here before it's $80 or so through Napa
http://www.napaonline.com/p/NF_LM487
http://www.napaonline.com/p/NF_LM487
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You're probably right...
Does not work on an LMM. There is no flasher module on an LMM. The turn signals are controlled by the BCM.
Just an FYI.
In the 03-07 trucks there is a prong you can cut off on one of the transistors to stop the hyper flash. No need to buy an expensive flasher. Ill take a picture of mine and post it here when I get a chance.
In the 03-07 trucks there is a prong you can cut off on one of the transistors to stop the hyper flash. No need to buy an expensive flasher. Ill take a picture of mine and post it here when I get a chance.
Yes, you have to take it to a dealer and have them call GM to build a custom calibration for the BCM. I forget what they call it, but the dealer should know. You may also talk to Ben about BCM programming. I'm sure he can fix it as well.
Thanks josh.
I called my local dealer today. Only 1 tech there I know and trust and he's out on vaca. So I'll get with him next week.