[bscott433]

Sounds like the new fuel pump or installation of it failed.

 

[WNG-2]

I am glad the ISG is ruled out. As I mentioned in the other thread, a member that bought a used 2018 had (what sounds like) a similar problem. I will put the link to the thread below. He solved it in post # 11 by spraying contact cleaner in the starter switch assembly.

2018 Tour manual will not try to start with new battery

 

[Earthdog]

I am glad the ISG is ruled out. As I mentioned in the other thread, a member that bought a used 2018 had (what sounds like) a similar problem. I will put the link to the thread below. He solved it in post # 11 by spraying contact cleaner in the starter switch assembly.

2018 Tour manual will not try to start with new battery

@bscott433 When questioned I am told the fuel pump is operating fine.

@WNG-2 The Dealer and Hondas stance on the kill switch assembly is since they are operating to turn over the starter fine it's not the switch. I really appreciate the info. It's so frustrating. Everything I have shared with the dealer the response is it's all fine. Clearly it's not all fine.

 

[WNG-2]

[USER=6345]@WNG-2 The Dealer and Hondas stance on the kill switch assembly is since they are operating to turn over the starter fine it's not the switch. I really appreciate the info. It's so frustrating. Everything I have shared with the dealer the response is it's all fine. Clearly it's not all fine.

Indeed. Donmac's problem was intermittent as recall. I was on the phone with him when he was making the purchase. It certainly won't hurt or cost much to spray some contact cleaner....

 

[AussieChris]

@bscott433 When questioned I am told the fuel pump is operating fine.

@WNG-2 The Dealer and Hondas stance on the kill switch assembly is since they are operating to turn over the starter fine it's not the switch. I really appreciate the info. It's so frustrating. Everything I have shared with the dealer the response is it's all fine. Clearly it's not all fine.

I don't think they should be so quick to discount either the pump or the kill switch. Proper diagnosis is required.

Fuel pump:
Saying the "pump is operating fine" sounds like they possibly just listened to it. Just because you can hear it running doesn't mean it's fine.

Did they actually check the fuel pressure as per service manual page 7-6 (you need a gauge and adaptors for that). The pressure should be 47 to 53psi. There have been cases where recall replacement pumps didn't run enough pressure, either because of a faulty pump or the tech left out crucial o-ring(s). Given the pump was recently replaced, I'd be suspicious.

Kill switch:
Claiming the switch must be fine because the engine cranks is a false assumption. Remember how the earlier model bikes could crank with the start button even with the kill switch off? Well this may be similar.

Honda fixed the problem by combining the kill and start button into one switch. However, it is still two independent switches (four wires come from that switch). The kill switch is connected to the ECM...

The Start Switch is actually connected to the Smart Control Unit...

Mechanically, you can't accidentally crank the engine with the kill switch in the off position but... what if the kill switch is faulty or shorted? I'm sure we've had one member here experience that exact problem.

Instead of just assuming, the dealer should do proper diagnosis and check the switch electrically. Just use a multimeter and check at the Red/Yellow and Light Green/Black wires at the Right Handlebar Switch 6 pin blue connector. Service Manual 22-7...

Unfortunately, some bodywork has to come off to get to that connector. It's located on the left side just below the speaker. But they probably had that stuff off to replace the ISG.

Finally:
Be aware that the starter (ISG) only cranks for 3 seconds regardless of how long you hold the button down and the engine doesn't start. I discovered this during my Lithium Battery testing. Here's the oscilloscope view of battery voltage (stock AGM battery) with the fuel pump disconnected (pressure bled off) and the start button held down continuously and no engine start...

At exactly 3 seconds the ISG cuts off. This can lead you to thinking there's an electrical problem when it's actually normal behaviour.

Dealers really need to do logical diagnosis rather than repair by replacement and guesswork.

I hope you get it sorted soon EarthDog.

 

[Zee Fifty]

Modern engines with ECUs, like your Goldwing, require certain conditions, from sensors, to be met while cranking to start. If these very specific conditions are not met the ECU WILL NOT COMMAND the fuel injectors or spark plugs to fire. I believe this is what is happening to your bike.

Fuel Pressure is one of the conditions…. even if you took a hose off and it flowed like no tomorrow and it seems good. It may not be good. If these very specific fuel pressure requirements are not met the ECU will not let it start.

The other condition that I’m aware of would be the Crank Position Sensor…. If something is wrong there…. bad sensor, connector, broken wire…. same thing…. The ECU will not command the fuel Injectors or spark to occur.…

My money is on something like that.

Unless the dealer specifically checked the pressure …. They can’t say it’s fine. ….. there has been many many cases of bad pumps and poor installs that cut an o-ring in the pump that causes this exact problem… this why we are just trying to make sure the pressure was tested.

My guess is if you pull a spark plug after you attempt to start it for a while you will see no spark and you won’t even have any gas on the plugs.… they will be dry….. complete no start condition.

There are probably many other things that would cause a no start condition while cranking. I can’t imagine Honda would not have a troubleshooting flowchart of everything to verify for this condition available for the dealer. This is a head scratcher. It seems to be a common issue to troubleshoot.

 

[Earthdog]

Modern engines with ECUs, like your Goldwing, require certain conditions, from sensors, to be met while cranking to start. If these very specific conditions are not met the ECU WILL NOT COMAND the fuel injectors or spark plugs to fire. I believe this is what is happening to your bike.

Fuel Pressure is one of the conditions…. even if you took a hose off and it flowed like no tomorrow and it seems good. It may not be good. If these very specific fuel pressure requirements are not met the ECU will not let it start.

The other condition that I’m aware of would be the Crank Position Sensor…. If something is wrong there…. bad sensor, connector, broken wire…. same thing…. The ECU will not command the fuel Injectors or spark to occur.…

My money is on something like that.

Unless the dealer specifically checked the pressure …. They can’t say it’s fine. ….. there has been many many cases of bad pumps and poor installs that cut an o-ring in the pump that causes this exact problem… this why we are just trying to make sure the pressure was tested.

My guess is if you pull a spark plug after you attempt to to start it for a while you will see no spark and you won’t even have any gas on the plugs.… they will be dry….. complete no start condition.

There are probably many other things that would cause a no start condition while cranking. I can’t imagine Honda would not have a trouble shooting flowchart of everything to verify for this condition available for the dealer. This is a head scratcher. It seems to be a common issue to troubleshoot.

<<My guess is if you pull a spark plug after you attempt to to start it for a while you will see no spark and you won’t even have any gas on the plugs.… they will be dry….. complete no start condition.>>

I am picking up the bike tomorrow to move to Southern Honda Powersports next week. I'll have it for the weekend to try this to see.

The dealer that has it (today) called me and said Honda Tech Line said to replace the PCM since the ISG made no difference.I am hopeful Southern will be better than my local dealer.

 

[Zee Fifty]

I would advise to ask the dealer why they think your fuel pump is fine and verify they did indeed check the fuel pressure. Run this specific issue to ground and put that puppy to bed.

I assume all the fuzes have been pulled and tested. If not they need to be.

Then your at the mercy of the Honda troubleshooters I suppose if you don’t know how to test the start stop switch and put that puppy to bed.

I‘m not sure I would bother pulling a plug to verify no spark and no fuel…. I think it’s obvious you’re in a crank no start condition and you won’t learn anything useful…. You’ll essentially just verify your in a crank no start condition.

We have seen some problems with fuel pumps and start stop switches … so we tend to concentrate on those items first. However, there is a long list of issues that could cause it.

 

[WNG-2]

This bike has under 24k miles. Has there been any significant documented failures of the parts discussed in this thread, at that mileage? The three second timeout that @AussieChris described sounds very similar to the problem @donmac was having with the used 2018 with 36k miles. That problem was cured by spraying contact cleaner in the starter switch assembly. Good luck. Hopefully you have better luck at dealer number two, and they check the simple stuff first on a low mileage bike before chucking Two Thousand dollar part$ at it.

 

[Wild Turkey]

I thought i replied to this problem but here goes. My 2022 engine light came on as i was exiting the freeway. I parked it went inside when i came out it would not turn over. Had it towed to my house replaced battery and checked fuses and it would still not turn over. Towed to dealer they stated it was the isg but i would have to pay for it because i have a trailer hitch on my bike. I advised them the hitch has been on their 2 years with no problem.
They claimed because of the non honda accessories that my extended warranty would not cover it. Well after a month of negotiations they decided to install a new isg. Well guess what that wasn't the problem. They they told me the ecm computer would be next. Long story short after 3 month i had to pay for both parts 4800.00 to get my back from the dealer.l They said they disconnected the wiring for my hitch and that the 2 parts would be covered for 1 year if i didn't hook the trailer hitch. Wow what a bunch of bull ****. Just a word to the wise for you all that have alot of extra lights/etc on your bike be for warned.

 

[Earthdog]

I thought i replied to this problem but here goes. My 2022 engine light came on as i was exiting the freeway. I parked it went inside when i came out it would not turn over. Had it towed to my house replaced battery and checked fuses and it would still not turn over. Towed to dealer they stated it was the isg but i would have to pay for it because i have a trailer hitch on my bike. I advised them the hitch has been on their 2 years with no problem.
They claimed because of the non honda accessories that my extended warranty would not cover it. Well after a month of negotiations they decided to install a new isg. Well guess what that wasn't the problem. They they told me the ecm computer would be next. Long story short after 3 month i had to pay for both parts 4800.00 to get my back from the dealer.l They said they disconnected the wiring for my hitch and that the 2 parts would be covered for 1 year if i didn't hook the trailer hitch. Wow what a bunch of bull ****. Just a word to the wise for you all that have alot of extra lights/etc on your bike be for warned.

@Wild Turkey So they ultimately replace the ECM and the ISG they told you was not bad previously?

 

[Earthdog]

Here is a video now that I have it home.

Things I have done since I brought it home today:
Check 2 white cap fuses fine
Checked all fuses
Smell Gas
Checked battery 13.4amp

Video of trying to start

 

[Earthdog]

PLEASE DISREGARD @AussieChris help me realize the Service Writer quoted the wrong part.

When I picked up today to take to new dealer the mechanic said he believes it needs a new (and to tell the other dealership I am taking it to):
HONDA OEM CONTROL UNIT, FR. | 38950-MKC-A11

Honda Control Unit

 

[AussieChris]

When I picked up today to take to new dealer the mechanic said he believes it needs a new (and to tell the other dealership I am taking it to):
HONDA OEM CONTROL UNIT, FR. | 38950-MKC-A11

Honda Control Unit

Wow! They are really grasping at straws.

I cannot see how the Front Control Unit (FCU) has anything to do with the bike starting or running. The FCU handles lights, turn signals, grip heaters, windscreen adjuster, and front shock dampening. More below.

Thanks for posting the video. That is very strange behaviour and I've never seen a bike automatically try to restart like that. So I have no real idea but seeing that behaviour, I would not have changed out the ISG (it's just doing what it's told).

The only control modules involved are the Smart Control Unit (SCU) and the Engine Control Module (ECM). The start button is connected to the SCU and the ECM commands the ISG to start. The SCU talks to the ECM via the Frame CAN bus (serial data like a LAN) so it's a bit hard to troubleshoot that area. One of the two modules decides what to do if the start button is pressed. Eg. Is the engine already running, is this an emergency start procedure, is the bike in neutral, those sort of things.

This diagram shows everything involved in starting (and the FCU is not part of it)...

So in terms of modules, it can really only be the SCU or ECM (both expensive). An SCU replacement also involves replacing the Electronic Steering Lock (ESL).

I don't have any answers but I'd be measuring voltages (probably using an oscilloscope because they will be transient) at every point in that diagram to rule out battery, fuses, relays, and wiring before spending big on an SCU or ECM. It's a bit harder when it comes to the wiring between SCU and ECM. The Red and White wires above are the CAN Low and CAN High data connections and the Blue is listed as "S-Net". The wiring between the ISG is tge White LIN (Serial data but lower speed than CAN), and the White/Blue Inhibit line and the White/Orange "Anticip" line. Other than continuity tests, I wouldn't know what to expect on those wires.

Sorry this got complicated but I just wanted to show that the Front Control Unit being proposed by the dealer is not involved.

 

[Earthdog]

Wow! They are really grasping at straws.

I cannot see how the Front Control Unit (FCU) has anything to do with the bike starting or running. The FCU handles lights, turn signals, grip heaters, windscreen adjuster, and front shock dampening. More below.

Thanks for posting the video. That is very strange behaviour and I've never seen a bike automatically try to restart like that. So I have no real idea but seeing that behaviour, I would not have changed out the ISG (it's just doing what it's told).

The only control modules involved are the Smart Control Unit (SCU) and the Engine Control Module (ECM). The start button is connected to the SCU and the ECM commands the ISG to start. The SCU talks to the ECM via the Frame CAN bus (serial data like a LAN) so it's a bit hard to troubleshoot that area. One of the two modules decides what to do if the start button is pressed. Eg. Is the engine already running, is this an emergency start procedure, is the bike in neutral, those sort of things.

This diagram shows everything involved in starting (and the FCU is not part of it)...

View attachment 497948

So in terms of modules, it can really only be the SCU or ECM (both expensive). An SCU replacement also involves replacing the Electronic Steering Lock (ESL).

I don't have any answers but I'd be measuring voltages (probably using an oscilloscope because they will be transient) at every point in that diagram to rule out battery, fuses, relays, and wiring before spending big on an SCU or ECM. It's a bit harder when it comes to the wiring between SCU and ECM. The Red and White wires above are the CAN Low and CAN High data connections and the Blue is listed as "S-Net". The wiring between the ISG is tge White LIN (Serial data but lower speed than CAN), and the White/Blue Inhibit line and the White/Orange "Anticip" line. Other than continuity tests, I wouldn't know what to expect on those wires.

Sorry this got complicated but I just wanted to show that the Front Control Unit being proposed by the dealer is not involved.

The mechanic said ECM but I see the Service Writer gave me a quote for what you noted was the wrong part.

@AussieChris Very impressive response Thank you!!!! Any chance you can give me the correct Honda part number for the ECM? I am not finding the ECM for 2018 and up.

 

[AussieChris]

The mechanic said ECM but I see the Service Writer gave me a quote for what you noted was the wrong part.

@AussieChris Very impressive response Thank you!!!! Any chance you can give me the correct Honda part number for the ECM? I am not finding the ECM for 2018 and up.

Sent a PM. But it's item 09 on the Control Unit page of the parts lists.

For 2018 DCT models...
DCT Tour and DCT Tour airbag models:
38770-MKC-A01
DCT Bagger model:
38770-MKC-A11

Manual shift models are different again...
M6 Tour:
38770-MKC-A21
M6 bagger model:
38770-MKC-A41

For a DCT, it would be wise to check what number you already have because it varies with region and year, and the ECM and TCM need to match.

 

[Fred H.]

It sounds to me like they are trying to find the more expensive parts on the bike to blame and replacing them first. This is not good troubleshooting. Before they start blaming it on the ECM, TCM, or any other electronic boxes, they really should check the fuel pump, and pull a plug and see if they are getting spark. If the plug is getting spark and there is no fuel, then it's probably a bad fuel pump.

I'd tell the dealership that you will refuse to pay for any parts they replace that later turned out not to be the cause of the problem.

 

[mrjava]

Since you had to pay for the parts, did they return the parts to you?
Also, would it be possible to get the technician notes for all the troubleshooting?
Seems like you paid for it.

 

[Earthdog]

Since you had to pay for the parts, did they return the parts to you?
Also, would it be possible to get the technician notes for all the troubleshooting?
Seems like you paid for it.

I have not paid for any parts. They pulled ISG from a loaner bike.

 

[Fluke189]

Unfortunately can-bus vehicles can be disabled by nearly any malfunction. A light bulb bad can render a vehicle no start. Can-bus is great when it works, when it doesn't, good luck. The data lines get corrupted, the whole system doesn't know what to do, so does zilch.
Good luck, the whole troubleshooting technique we've all used for 100yrs is near worthless. Junk and obsolete the day it's sold and repair is a costly exercise in guess and trial and error. I saw that immediately when they released the 2018-up and due to that would never want one. Don't want a new car or truck either. Too complex with the crap, and can't be repaired.