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Road King Fuel Pump Issue

I probably would not go through the trouble of relocating the safety device but a Maxi fuse would be the way to go if you don't mind doing the work. The Maxi fuse holder is pretty large and comes with thick leads that would require a beefy soldering iron to wire in.

Those 16 flashes are strange. In most all other cases, error codes are read out in 1st digit then 2nd digit. So nine flashes should be the most you would error see (error code 9X or X9)

You may want to take a look at what size the CB breaker you have in bike right now. See if the studs & eyelets on the breaker are discolored from heat.
 
I got the new fuel line and breaker. I will be putting it back together tonight and will post the results. Just wanted to stay in touch and say thanks again for helping.
 
Be sure those wire eyelets on the breaker are clean and crimped good. If they are discolored in any way, it means the eyelet crimp to wire is bad and they must be replaced. It is always good to use an internal star lock washer on those studs to give it good bite. It also keeps the eyelet from rotating out of position when you tighten them.
(always first install internal lock washer, then wire eyelet, then split lock washer then nut. No di-electric grease before tightening)
 
Ok. Replacing the breaker did not produce the results I had hoped for.
At this point I cannot get voltage to pin 30 of the Fuel Pump relay. The Grn/Yel wire from pin 30 powers the Fuel Pump, injectors and coil. I have disconnected all of them.
OEM Manual Troubleshooting chart says No power on pin 30 = Short on Red/Org wire
Org/Red wire is Pin 87 on the relay and goes to Fuel Pump fuse and Diag Connector. Not very long wires and I do not find a short.
I have tried 3 different relays.
Run switch off I get 12v on coil Pin 86, Run Switch on I get 12V on both coils Pin 86 and 87
Also have 12V on pin 87 of the relay from Fuse.

I can apply 12V directly to fuel pump and get it whine, so pretty sure it's not the pump.
Inspected Yel/Grn wire around the injectors and coil, no shorts. I have not pulled back all of the black jacketing to inspect the entire yel/grn run.

No blown fuses.

What could be causing the Fuel pump relay to not pull in and apply voltage to Pin 30?
 
I think there should be a grn. wire to the relay also.Have you checked to make sure it is good.I don't have a schematic but I think you have to have the grnd. to make the relay close to give pwr. to the pump.Hoopie will know for sure.
tourbox
 
FLHPI said:
What could be causing the Fuel pump relay to not pull in and apply voltage to Pin 30?
Click to expand...

The problem is not a short on the yellow/green wire. When I use the phase "a relay picks" I mean that both voltage and a ground signals are being applied to the relay coil in order to make the relay armature pull in or "pick". The fuel pump will only run when the fuel pump relay is picked.

Remember that on a perfectly running bike two conditions must be met for the fuel pump relay to pick. 1st condition=> battery power (12volts) must be applied to pin 86 of the fuel pump relay. That power comes from the RUN/Kill switch. When the RUN/Kill switch is set to the RUN position, power is applied to pin 86 of the fuel pump relay. The second condition that must be met is you need a ground signal on terminal 85 of the fuel pump relay. That ground shot comes from pin 23 of the ECM. Pin 23 of the ECM supplies a ground shot to terminal 85 of the fuel pump relay. With a ground supplied to pin 85 AND power supplied to pin 86,, the relay will pick.

So as far as the fuel pump relay is concerned, the rider supplies the power (using the Run/Kill switch) and the ECM supplies the ground shot. So both the rider and the ECM have a say into whether the relay will be picked at any given time. When the rider flips the Run switch to RUN, he sends 12 volts to pin 86 of the fuel pump relay and also sends 12 volts to pin 26 of the ECM. Sending battery voltage to pin 26 of the ECM, tells the ECM you flipped the RUN/Kill switch to the RUN position. At this moment there is no crank sensor signal present at the ECM so the ECM knows the engine is not spinning. If the ECM does not see the engine spinning, it will not allow the fuel pump to run continuously. The ECM will only ground shot the fuel pump relay for 4 seconds to prime the fuel rail. Then once the engine cranks and starts running, a crank sensor signal is established at pins 28 & 11 of the ECM. The ECM now knows the engine is spinning and will re-ground shot pin 85 of the fuel pump relay. The pump now runs in continuous mode.
So if you happen to be sitting at a traffic light with the engine running and you let out the clutch too fast and stall the engine, the fuel pump relay immediately releases because the ECM no longer sees a crank signal. But in this case the fuel rail is already primed so an ECM boot process is not necessary. Just hitting the crank switch re-starts the engine.

Do not continue to troubleshoot your problem until you fully understand this boot sequence and the conditions needed for the fuel pump relay to be picked. The reason I say that is because the voltages on the fuel pump relay will change depending on if your in a 4 second boot process, a POST 4 second boot process with engine running, or a post 4 second boot process with the engine NOT running.

So lets break down what you said earlier. You said "Run switch off I get 12v on coil Pin 86, Run Switch on I get 12V on both coils Pin 86 and 87".
I will assume you were in the "post 4 second boot process" with the engine not running. I will also assume the fuel pump relay was removed from the bike. If that is the case, all the measurements you made are invalid. The fuel pump relay must be installed to get valid readings.

Check it again. Having 2 meters hooked up at the same time would allow you to see that sequence take place. The fuel pump relay must be installed. With the RUN/Kill switch in the RUN position,,, your post 4 second boot sequence,,,engine is not spinning => you should read 12 volts on both pin 86 and 87 (relay not picked). But during the 4 second boot only, you should read 12 volts on pin 86 and 0 volts on pin 85 (relay picked). As soon as the 4 second boot has passed, pin 85 should go from 0 volts to 12 volts (relay not picked).
Does this happen.
 
Good stuff, and on the money. You are a good man Hoop. Remote troubleshooting is an art. OP, Hoop will get you there if you are careful and patient.

I have quite a bit of experience with remote troubleshooting vintage audio gear. I can recognize good help when I see it. You are getting good help, for sure.

I return you to your regularly scheduled programming...

Good luck,
Rich P
 
RibEye said:
I have quite a bit of experience with remote troubleshooting vintage audio gear. I can recognize good help when I see it. You are getting good help, for sure.
Good luck,
Rich P
Click to expand...

I have read all your posts and your always on the money also Rich. I have a lot of experience at it because I am too cheap to pay someone to do it for me!:)
 
Glad to say I was able to get the bike running tonight. Was able to make a few laps around the block without it dieing.

I am unable to say what I did to fix it. After the troubles yesterday, I pulled the tank again. Un- cable tied as much of the harness as I could and began checking for shorts, again. Having found none, I hooked up the fuel pump, with the tank off the bike, put the battery back in and viola' I got the power to the pump. All this with the harness hanging off the bike.

So I began the process of tying the wires back up, checking for fuel pump power after each section was strapped down, thinking if I had a short or broken wire I would at least know what section was last touched.

I do however have a check engine light now and several codes.
24-Front Coil, 25-Rear Coil, 16-Batt Pos Voltage, 35-Tach, 42-Cam Shaft Sensor.
Not to sure about coil messages since I have a brand new coil, wires and plugs. And the new coil measured the exact same as the old. Running through the Error 16 steps is also proving confusing as most steps are looking for Voltage drop, which I do not have in any of the steps.
Thinking of going through charging system tomorrow and inspecting the wiring around the voltage regulator, thinking that could be the cause for the first 3 codes.

I designed printed circuit boards for several years, so thankfully I know my way around a schematic and while I do not have the electrical engineering knowledge of how and why stuff works, I have enough general knowledge to troubleshoot (I hope) with assistance from great folks like you and a good manual.

I appreciate you breaking down the process, and I do understand what you are saying, I do see the variations of voltage on the relay depending on the current state. All my tests yesterday were with the engine not running.

I am calling today a success though, because it started/restarted and I rode it :)
Now just to continue trouble shooting until I get all the kinks worked out.

Thanks Again to you guys for taking time out of your day to help me. It is VERY appreciated, and I too am way to cheap to pay someone to do something, I hope I can do.
 
Sounds like a rubbed/pinched wire then. You are on the right track and almost home. Keep us informed.
 
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