I have tried to use a Gerbing MP (the newer microprocessor one - serial number ends in MP) single controller for a Gerbing jacket liner on my R90/6. The is the second one (first one replaced by dealer) and the problems are identical with both. After less than a mile, it flashes red, indicating a short or overload. But there really is none. On my R75/7, I have a dual controller (MP), and there is no problem. The R90/6 has an electronic VR, and an S fairing with voltmeter, and I can see it regulates just fine. Both bikes have the controller with a Gerbing 2ft extension, after the controller, running under the tank back to the seat area, where I plug in my vest with or without a 4 ft coil. With either my wife's jacket liner and coil or with mine, it flashes red. They are both new so either they both are bad (not likely) or the controller is bad. If I don't use the 2 ft extension, it flashes red. If I move the controller to my R75, it flashes red. So with either liner, any or either or no cord, either bike, it (i.e, both did this) flashes red. The only time it doesn't flash red is when nothing is connected to it. Not very useful Has anyone gotten a Gerbing single MP controller to work on an airhead? Or on any bike? Or are they really making a lot of bad ones? I find this hard to beleive, but I'm about out of ideas. I talked to Gerbing and they said there should be no problem with running both a 2ft extension and 4 ft coil, and indeed there is none with the dual MP controller. They also said they have never heard of any problems with their controllers, so implied it must be me, but every piece electrical, from the battery harness to the controller and back, is from Gerbing.