New ECM and Fuel Pump

[MachineCobb]

I have a 1993 GL1500 Aspencade. After riding 300-400 miles in a day with a group… the next day it would only die after starting. I just put a new fuel pump in the bike from Allballsracing prior to the big ride. After diagnosing that the fuel pump had no power I realized the ecm went bad. I have ordered an ecm from a reliable vendor online, however I’m nervous about replacing the fuel pump. Which fuel pump won’t blow another ecm up, or how can I prevent that? I remember at some point reading a post about diodes and relays but I couldn’t find the op. Also is there not a pump that is safe to use as a replacement at a reasonable price? This is my first Goldwing, she’s my baby… but I’ve only ridden maybe 1000 miles on her, and that’s after a full service about six months ago. Hopefully the knowledge on this fix is here in the forums. Thanks!

[WingAdmin]

I have a 1993 GL1500 Aspencade. After riding 300-400 miles in a day with a group… the next day it would only die after starting. I just put a new fuel pump in the bike from Allballsracing prior to the big ride. After diagnosing that the fuel pump had no power I realized the ecm went bad. I have ordered an ecm from a reliable vendor online, however I’m nervous about replacing the fuel pump. Which fuel pump won’t blow another ecm up, or how can I prevent that? I remember at some point reading a post about diodes and relays but I couldn’t find the op. Also is there not a pump that is safe to use as a replacement at a reasonable price? This is my first Goldwing, she’s my baby… but I’ve only ridden maybe 1000 miles on her, and that’s after a full service about six months ago. Hopefully the knowledge on this fix is here in the forums. Thanks!

If the fuel pump has died, the 1500 will gravity feed fuel...as long as there is enough fuel in the tank to keep the fuel level above the carbs.

Two things:

1. The ECU itself is not bad - just the transistor that it uses to activate the fuel pump. It's actually cheap and relatively easy to fix. Have a look at this topic where there is a step-by-step guide: ECU Fuel Circuit Failure - the transistor shouldn't cost more than a couple dollars to replace.

2. The transistor typically goes bad because the fuel pump has drawn too much current. Plugging a new ECU into it will likely end up with another ECU with another blown transistor. Make sure the fuel pump is not a problem first.

[bellboy40]

You didn't say how you determined that the ECU was bad. Before condemning the ECU, make sure you have properly tested it for voltage at the input to the pump. There will not be any voltage to the fuel pump unless the starter is turning the engine over or it is running. Just turning the ignition switch on will not put power to the fuel pump. The engine must be turning over.

[MachineCobb]

The engine turns over. The voltage at the pump coming from the ecu was less than 6 volts at times and occasionally measured 11 volts. After utilizing the troubleshooting bible i have for my bike it stated the ecu was bad. After my testing it showed the ecu was bad as well.

[bellboy40]

Ok, I was just making sure you were not chasing a trouble that was not there. Sometimes it is easy to get off track. If you are sure the ECU is bad, proceed with either replacing it or try to repair it using the method in the link (viewtopic.php?p=72687#p72687) that was posted by WingAdmin.