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Fuel System light didn't iluminate

3K views 20 replies 6 participants last post by  Pim205GTI 
#1 ·
Hi,

I'm a newbee in this forum and also a new owner of a CX 500 turbo. I'm living in the Rhein-Main area in Germany.

Now I have a problem with the Fuel system light and the self test of the ECU. After Oil changing i have started the machine to warm them up. But after a view minutes machine stopped and now it didn't run. I have tested several things (main relais, fuel relais, fuel pump) it seems that the fuel relay gets no ground from the ECU unit. Now I found, that the fuel light didn't flash after ignition, like described in the owner manual and also I did not get an failure code from the ECU. Further the "W" LED didn't also iluminate for round about 2 seconds like described in the turbo manual. Did have anyone an Idea what are the reasons for this fault?

Hoping you have answers

Regards

Matthias
 
#2 ·
Sounds like you lost power to the ECU. I'd remove and reconnect the large connector on the ECU. After that, start checking for disconnected or damaged wires.
Do you have the orange emergency stop switch on the right handlebar control (might be only on US models)? Those can get very flaky and shut down the bike. When you turn on the ignition, how many segments of the TURBO meter are lit up?
 
#3 ·
Hi George,

thanks for your answer.
1. Reconect and conect, same problem
2. Orange emergency switch runs well
3. Turbo meter shows one segment
4. Wires will be checkt..... come back if i had done this
Did you know which cable are the power suply for the ECU?

By Matthias
 
#4 ·
Only the center segment lights ups if the emergency switch is off or failed. I get about 4 segments out from center (left and right) with switch on.

Also, the fuel pump will not prime for 3 seconds and the "fuel system" light will not turn on for 3 seconds if that emergency switch has failed. You CAN however crank the engine over and the rest of your lights will work.

The orange emergency switches on the 500 are known to be intermittent or fail completely. I need to take mine apart and clean it before I start riding this season...I can tap it and the bike will shut down. It's possible the problem if further down in the wiring, but I'd suspect that switch first.
 
#5 ·
Hi George,

unfortunetly the Problem wasn't the emergancy switch, I have opened them and cleaned them. Problem is still present. I have checked all the plugs behind the cockpit they shown in good condition. But now all the turbo lights are iluminating, little success. Tomorrow starting up with searching deeper in wiring.
 
#7 ·
Which one is the "Tip over sensor" and how can i test it, and what is the function of it? I have searched in the turbocharger manual and in the owners handbook and didn't found a sensor named "Tip over" Sorry but I´m realy unscilled by this sort of a bike.
 
#8 ·
Think tip over sensor is Ok because:
1. Main relais works
2. Fuel pump relais works (I tested them by changing with the main relais)
3. Fuel pump relais didn't get ground from the ECU
4. Fuel control light wire didn't get power from the ECU
Need more suggestions for testing, at the moment I'm stumped
 
#9 · (Edited)
That sensor is designed to shut down the bike in case of an accident. Your fuel pump relay won't be energized if the sensor thinks the bike a laying on its side. There is a detailed process to test it on page 22-12 of the shop manual.
Do you have the shop manual with wiring schematics for the bike?

If not, try here:
manuals

Click on the 2nd folder "Factory Service Manuals" and then click on the 500T manual.

I think you need a Google account to access that page.
 
#10 ·
Ok, thanks, i will try and come back, last two hours i have cleaned the bike by searchin an broken cabel or somthing else. Nothing found!
 
#11 ·
Ok have checked the tip over sensor. He has the allowed voltage like discribed in the manual. By the logic that the tip over sensor access the main relais he can't responsible for my fault. Now I'm reading the manual mayby i will find further hint's.
 
#12 ·
By reading the manual troubleshooting section 24-4, I have to replace the ECU because voltage is on pin one and two like written:( So i have decided to open the "black box" photos attached. Electronics Circuit component Electronic component Technology Electronic engineering
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I think I have found the fault in the bigger photos upper left corner you will see burn marks. What's your opinion?
 
#21 ·
By reading the manual troubleshooting section 24-4, I have to replace the ECU because voltage is on pin one and two like written:( So i have decided to open the "black box" photos attached.
View attachment 10739
I think I have found the fault in the bigger photos upper left corner you will see burn marks. What's your opinion?
This "area" is the power regulator. Input battery with voltage spikes from everywhere ( sparkplugs, main voltage regulator etc ) to the 5 volt necessery to run the computer.

Especially important is the over voltage/spike diode which in this picture is the black disc with to protruding thick wires. It is clearly damaged.

If unregulated voltage has reach the 5 volt system then this whole unit is toast :(

Maybe you can donated it to science and I will run some test on it



If I can repair it for you I will let you know ;)

Pim
 
#15 ·
Ok, stator didn't tested until yet. How can i do this without an running machine? From where to which place i should solder in a jumper wire?
 
#16 ·
Near the batery there is a white connector with 3 yellow wires. Between these wires, you should be have less than 1 ohm and no continuity between each yellow wire and ground.
The next step, when the motor running, between each wire there is a voltage 40VAC for 3000RPM.

I suppose the jumper is for replace the burning connection.
 
#17 ·
From the -V Bat terminal, I'd take a wire to the ceramic capacitor (C2) and then to the electrolytic capacitor above (14 stamped on top). Double check C2...it appears the trace attached there but I'm not 100% sure from the picture.

If you have no soldering skills, please take it to someone who does...you'll make things much worse if you don't know what you're doing.
The electrolytic capacitors which look like little canisters are the type that fail with age. I'd at least replace the one with the brunt trace going to it. Also look closely at all of them. If you see any oil or the metal top portion bulging, it must be replaced.
 
#18 · (Edited)
I had a similar problem. Found a poor connection in a multi-pin connector to the left of the headlight behind the fairing. Drove me nuts searching for it. Glad it wasn't as involved as this one...

Jan
 
#20 ·
Solving the problem.

ECU was damaged, after changing them, machine works well. I think, the root cause was disconection the battery by running the machine (stupid idea).

Thanks for your help.

Matthias
 
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