| Author | Message | ||
     Devondunit |
 So I had to jump my dead battery off of the car, big mistake... now that I have a new battery and replaced my battery and fuel pump fueses that where blown I couldn't get it to start, just cranks over and fuel pump wouldn't prime. I replaced the fuel pump with a salvage one that is guaranteed to be operational, and still have the same problems. when I crank it for a few seconds the fuel pump fuse blows and it still doesn't start or prime. the screen also says system voltage even with the new battery so... could it be my rectifier is fried, or a relay shorting out? I am hitting proverbial brick wall and about to set my garage on fire. | ||
| Devondunit |
btw... replacing fuel pump was a treat!  | ||
| Froggy |
If the car was running when you jumped the bike, your regulator is now likely shot. If the car was off it should not have damaged anything, at that point it is just a giant battery. I can't see how that would cause your fuel pump issues though. | ||
| Brumbear |
I have honestly jumped hundreds of bikes off a car running and not running it has never been an issue. Voltage is voltage bike redtifier works the same as a car just more amps that would hurt your battery not your reg. | ||
| Brumbear |
You have a Battery problem or starter first peak problem or a bad ground IMO | ||
| Brokengq |
Brumbear, I think you may have just been lucky over the years. First time I tried to jump one of my Harley's off from a running car I had to put a stator and VR in it. Buddy fried his Shadow the same way. Too many amps going through the system too quickly will burn it up instantly. The sudden surge of power will blow things like the ECM right out. Could also fry/melt wiring harnesses from what I've heard. It also depends on the car though. I jumped it off of my Tahoe, that turns out 145 amps. That's a lot of juice for a bike to try to regulate. You would have a lower chance of damage off of a 90 amp Honda, for example. I still wouldn't suggest it though. Power surges can cause house fires, and jumping off of a running car just purposely induces a power surge to the bike. Food for thought. (Message edited by brokenGQ on July 10, 2014) | ||
| Devondunit |
Thanks for the input, I severely hope I didn't damage the stator, I replaced it with the EBR upgrade last year! Anyone know where to get a replacement VR other than Harley? | ||
| S21125r |
I don't have the electrical manual in front of me at work and electronics are not my strong skill, but sounds like you have a short on the hot side between fuse block and the fuel pump. Instead of powering the pump it sounds like it's shorting to ground and blowing the fuse as soon as power is applied. If it were a bad ground or an open circuit it wouldn't be blowing fuses. You should be able do a continuity test on the hot wire between pump and fuse to verify as I'm assuming the relay is on the ground side of the circuit (someone verify?). If that fails then I'd do a continuity test to ground up and down that hot wire until you find the source. When I get a chance to dig up my manual I'll take a look at that circuit and see if there is anything else to suspect. | ||
| S21125r |
I just remembered that the pump is pulse width modulated so there is no mechanical relay - the ECM pulls it to down to ground to cycle it on and off. Here's a related thread that I commented in a long time ago. http://www.badweatherbikers.com/buell/messages/290 431/705083.html?1380506536 Relevant info in there is to: Check to see if you have power at the Orange/Grey wire (with new fuse and key on). If not then run continuity checks on the O/Gy wire until you find the short. The black wire is the ground but that shouldn't be the source of your fuse blows. The Brown/Yellow wire goes back to ECM pins 27 and 28 and that's what does the modulation on the ground side (turns pump on/off in milliseconds time scale). You could jumper it to ground to see if it cycles on but I think your problem is on the hot side. The Yellow/Red wire I think is for the fuel level sensor so ignore. All else fails (as a quick test) jumper from battery + to O/Gy of the pump connector and battery - to the BN/Y of the pump connector. If it doesn't power on then the pump is probably the source of the short. If it does power on then the pump is good and your short to ground is in the O/Gy wire somewhere. | ||
| Devondunit |
Ok, I will check that when I get home. That might explain the system voltage readout. | ||
| Devondunit |
So I did continuity to black wire from frame: good Continuity from fuse to O/G: good Swapped out EBR ECM for stock: no change Voltage on O/G: 00.00 (The very first time I did it it showed 12v and started once for a second; but every time after, nothing...) VR? | ||
| Devondunit |
I also did O/G to ground and no short to ground.... | ||
| S21125r |
so no voltage to the o/g wire... Fuse blown again? Did you also try momentarily jumpering the pump directly to the battery to see if it will cycle? |
