OzSTOC

Honda ST1300 Section => Electrics & Electronics - Volts, Amps and Fuses ST1300 => Topic started by: DJW on December 21, 2020, 07:57:53 PM

Title: Fuel pump not engaging
Post by: DJW on December 21, 2020, 07:57:53 PM
After about three weeks in the bike shop, I have my bike back but still a no go.  I posted previously that it was a ECM issue but after having a loaner ecm delivered and tried the fuel pump still will not prime or engage when the ignition is on.  The bike will wind over but because the fuel pump is not priming, the bike wont start.  I am told that they have examined and tried every possible electrical diagnostic that they can think of and with advice from Honda.  All fuses, relays, connections, switches etc have been checked I am told.  The fuel pump was bridged and proven to work i am told, however once plugged back in to the wiring loom, its a no go.
So, the result is I have a bike that the fuel pump will not engage when the ignition is on so therefore wont start.  Any ideas from the brains trust????
Title: Re: Fuel pump not engaging
Post by: Jdbiker on December 21, 2020, 11:32:01 PM
Good thing you didn’t invest in a new ECM just to find that wasn’t the issue. I still think it’s a faulty connection or damaged wiring. Do you have a wiring diagram? Trace back wiring from fuel pump. Might have been able to help if you were in Melb.
Good luck 👍
Title: Re: Fuel pump not engaging
Post by: StinkyPete on December 22, 2020, 05:35:41 AM
My first check wouild be for voltage at the fuel pump wiring connections, but I would assume that's been done.
Do you have enough faith in your mechanic that they have properly investigated the issue, and not just said that they have?
Title: Re: Fuel pump not engaging
Post by: Jdbiker on December 22, 2020, 06:51:55 AM
If ECM has been eliminated as the problem, other things to check are ,

Fuel cut off relay
Engine stop relay
Engine stop switch
Lean angle sensor

Title: Re: Fuel pump not engaging
Post by: West Aussie Glen on December 22, 2020, 09:41:03 AM
It may be worthwhile reading this thread:-

http://ozstoc.com/index.php?topic=13796.msg1265480#msg1265480 (http://ozstoc.com/index.php?topic=13796.msg1265480#msg1265480)

As well as some strange systems the fuel pump didn't start.
Title: Re: Fuel pump not engaging
Post by: DJW on January 02, 2021, 09:16:34 AM
So, I have this week off.  All plastic comes off today to get in and around the bike.  Also forgot to mention that the battery is cactus, but I would have to assume that the bike shop used a good battery, not my crappy one that wont hold charge.  Off to get a new battery this morning and a trickle charger.
I am not a mechanic by any stretch, but I have a basic understanding if a wire is getting power or an earth is dodgy.  I know that the bike shop has said they checked everything they can, but my brain tells me to have a crack myself.  I have printed of the topics re the various suggestions and I guess its now a matter of trial and error to see if I can get the fuel pump to prime. If I cannot figure this out there may be a cheap ST1300 on the market at weeks end.
Title: Re: Fuel pump not engaging
Post by: ST2UP on January 03, 2021, 11:52:51 AM
So, I have this week off.  All plastic comes off today to get in and around the bike.  Also forgot to mention that the battery is cactus, but I would have to assume that the bike shop used a good battery, not my crappy one that wont hold charge.  Off to get a new battery this morning and a trickle charger.
I am not a mechanic by any stretch, but I have a basic understanding if a wire is getting power or an earth is dodgy.  I know that the bike shop has said they checked everything they can, but my brain tells me to have a crack myself.  I have printed of the topics re the various suggestions and I guess its now a matter of trial and error to see if I can get the fuel pump to prime. If I cannot figure this out there may be a cheap ST1300 on the market at weeks end.

I’m reasonably sure it will be a shorted wire in the loom that zigzags around under the seat.

I know this because it happened to me exactly as you have described  ;-*

I’m sure I put a thread with the fix here on the forum.....all I did was ID the problem but not the exact location of the issue as it occurred in the loom over a wire distance of about 2 metres.

My fix was to use a water proof fuse holder from the Fuel relay to the pump and install a 20amp fuse, this way if I get so inclined one day I can pull the fuse and replicate the issue to repair. I can almost guarantee I will never have the time.....this has worked for last 4 yrs without issue.

Cheers
Title: Re: Fuel pump not engaging
Post by: DJW on January 03, 2021, 01:04:03 PM
Hi, there are 3 wires of the pump, two brown and a green.  Which wire did you connect straight to the fuel relay and what position on the relay please

Sent from my SM-N975F using Tapatalk

Title: Re: Fuel pump not engaging
Post by: PC on January 03, 2021, 02:29:54 PM
http://ozstoc.com/index.php?topic=8672.msg102276#new (http://ozstoc.com/index.php?topic=8672.msg102276#new)
If I have done it Wright try this link
Title: Re: Fuel pump not engaging
Post by: West Aussie Glen on November 13, 2023, 10:34:11 PM
DJW did you ever solve the problem? Sounds like maybe your key wasn't deactivating the HISS?
Title: Re: Fuel pump not engaging
Post by: West Aussie Glen on November 13, 2023, 10:38:52 PM
Hi, there are 3 wires of the pump, two brown and a green.  Which wire did you connect straight to the fuel relay and what position on the relay please

Sent from my SM-N975F using Tapatalk
Green is earth
Brown is power to fuel pump
Brown with Black stripe low level thermister