If i had to guess, i would say an electrical issue, like bad battery cell / plate, or alternator not charging the battery sufficiently. Just a total guess on my part, though. Battery seems to be a common failure point when seemingly unrelated messages light up.

 

I was going to say the same thing if it wasn’t for the transmission suddenly downshifting?
Bill

 

There have been other reports of these three warnings when a torque converter fails - hope they find that it's just the battery!

https://www.ridgelineownersclub.com/threads/2017-transmission-system-problem-and-blindspot-monitoring-message.220954/#replies

https://www.ridgelineownersclub.com/threads/transmission-system-problem.243655/

 

Seems oddly common in 2017 (before your 9 speed) in the threads I've found:

https://www.ridgelineownersclub.com/threads/purchased-2017-ridgeline-and-now-dashboard-is-lighting-up-with-issues.244035/

Here's one on a 2019 (still pre-9 speed):

https://www.ridgelineownersclub.com/threads/transmission-p0741.241494/?post_id=3361676#post-3361676

 

Seems oddly common in 2017 (before your 9 speed) in the threads I've found.

Makes me wonder about the history of this scenario (same dash warnings) on units with failed torque converters - does the failing torque converter mechanically allow enough flex in the transmission to strain the CANbus connections, or is there another explanation?

I don't know if the simultaneous warnings in those cases also had the same fault code.

 

Gee, if it was a 6-speed the answer would be obvious, dump the vehicle and purchase a 9-speed! 😛

Sorry ATL RL, the devil made me do it! 😈

In all seriousness here is to just a weak battery?🤞

Bill

 

@BeshmoHandes
Yep....lots of 6 speed issues like mine on the surface.

The shop foreman did comment to me that in some cases one item triggers the event and the blind spot warning is just collateral damage (my words) ....it is like a sympathy code...it does not really mean I have an actual blind spot problem.

We did not discuss, in the few moments I had with him, any transmission/emissions relationship.

BUT....I know that from my previous training that if the trans has an issue and turns more revs per mile than prescribed....it is polluting more per mile than allowed and the OBD2 requirements dictate that a code has to be set and the CEL comes on.

Battery.....Transmission.......one day.......a week or two.....those are the variations I have to be prepared for......not a good feeling.

 

Well done by going to the dealer. Did they hook up the scan tool? Were the conditions dry during your trip? Hope it's the battery and nothing more. Do you park where the critters can chew the wires?

 

I left as they were taking the truck to the actual shop. I did not see any scan tool hook-up. They gave the truck to a tech that was working today (Friday) and will also be working tomorrow (Saturday). I limped to the dealer at about 4:15/4:30pm. Coming back the trip was 100 percent dry. I do not think we have a critter factor. Garage kept....no critters there....and for the past 5 days was parked in the parking garage at our resort. Not aware of any critters there.

Thanks for the comments

 

Well firstly I am sorry this happened to you.

Well done for having the presence of mind to take it straight to the dealer.

I think the downshifting was the RL preparing itself for limp mode.

I'm guessing / hoping it is a battery issue - multiple warnings lights, limp mode all point to that.

The fact that (correct me if I'm wrong) there were no symptoms or issues coming from the transmission or final drive on the journey makes me think a fault with those systems is more unlikely.

Back to the battery, could also be a failed / faulty battery fan - maybe the long journey you'd just been on caused an overheat condition in the battery via a faulty fan??

Good luck and please keep us udated.

 

Fingers crossed that it's a battery, my 2018 went wacko when the OEM battery bit the dust.

 

My 23-model battery was replaced at around 20,000 miles. It also did some weird stuff but no limp mode.

 

Partial update.....this is all I have so far....logic fault between tcm and pcm....intermittent. DRAT!

Intermittent faults are the most difficult to nail.

 

Or when inaccurate data is presented, like my currently experiencing a failure of the emissions system purge valve and an AWD CEL is being presented?

Bill

 

Code: U0100

A network/comm code

No obvious loose items.

Got data yesterday while acting up.

Today.....behaves perfectly.

Did one 10 mile test drive already.....normal.

They intend on spending more time with the truck.

 

That’s a tough one. I hate to say this, but it’ll probably be better for it to be worse so they can diagnose it when it’s happening. in cases like this, I always think of South Main auto where he finds an offending wire.

 

I have bad news..... that's also good news..... that still is bad news.

After not finding any concrete evidence, two technicians hopped in the truck with a scan tool so they can make recordings of the network.

At the tail end of their test drive the vehicle went into limp mode.

The difference between their experience and my experience is that they had a current fault that was present for the end of the drive.

My fault had been a momentary glitch that caused my truck to go into limp mode but the time they actually pulled information in their parking lot yesterday afternoon there was no present active fault..... only something in history.

That means in their case today when they tried to restart the truck it automatically started off in limp mode.

They have been on the phone with a Honda Tech Line today but as we all know it is Saturday and both dealership and tech line manning may not be at 100%.

So I'm not getting back my truck today and I told the dealership I understand it may not even be ready by Monday.

They know I'm supposed to leave for Florida on Saturday and that we need to get this nailed down.

I believe that since Honda tech line is involved this completely elevates the status of this situation.

The technician probably did the mandatory 15 or 20 checks called for when this code is present and based upon what I was told he physically touched a lot of things and did not find any dramatic evidence of a problem.

There are hundreds of connections in a car and unfortunately I've got one circuit that is a bit glitchy.

Unlike high current carrying wires is not going to be much evidence of arcing or sparking...... So they're going to really have to pay close attention and try a variety of things in my opinion to get this circuit to calm down and be stable.

I'm just thankful, once again, that this happened here in my hometown and not while I was hundreds of miles away.

 

I am sorry for your trouble and hoping your issue will be resolved quickly....

As I red through this thread,kept saying to myself that this issue is probably related to network/comm channel. I vaguely recall someone having a similar issue in the Maverick forum, when I had my Maverick. It turned out that some sensor broadcasted on the on the channels, that effectively blocked other system from communicating with ECU. That's how the ECU decided to shut off the engine in that case.

In your case, the alerts didn't reach that level, but just enough to trigger the limp mode. The source of the issue may not be some loose wire, it could be a faulty sensor in that network, or a faulty module. Again, I hope they'll find it quickly and get you on your way...

 

Sounds like a good faith effort to resolve the problem. Hoping it's something definitive.

Since the dealer is aware of your upcoming trip, have they offered you a loaner vehicle? If you're under the original manufacturers bumper to bumper warranty you should be entitled to one. Apologies if you addressed that and I missed it.

 

I am trying to be a good and polite customer right now.

They already know that I have an OEM background and have been having very frank discussions with me.

They have not offered a loaner yet and I have not asked....yet.

I am retired so there is no pressure to go to work at 8am on Monday.....but they absolutely know I just came back from Florida and have a departure one week from now.

If we get close to my trip date then I will ask about the loaner for sure.

I have been very gracious and gentle with them and I think they appreciate the fact I have not been yelling and screaming because each time we turn around.....stuff gets deeper and we don't yet know the root cause.

I even expressed gratitude for them looking at it at 4pm on a Friday and spending "all day" with it on a Saturday.

Looking up the details of my B-B coverage and any possible Honda Care angle is on my "to do" list. (I have 8/100 Honda Care)

 

Controller Area Network (CAN) is a very robust and fault-tolerant data network, which is why it has become the standard protocol for noisy environments. Unfortunately, all networks are susceptible to damage to their physical layer.

When I first started reading this, my first thought was that a battery plate had fallen away, but it seems like we're beyond that now.

I really hope they can get you to a resolution that's satisfactory for you.

 

You deserve a good outcome to this situation, I hope you get it.

 

Some info on U100 - it appears this code is generally a "communication malfunction" code, and I can see multiple variants of it in the service literature. It seems like multiple modules can report the code, so the code itself is more useful when the reporting module is known. You mentioned PCM-TCM, so I assume one or both of them reported that code.

I'm guessing that data for the blind spot system and emissions control are on the same network, so loss of communication would set those lights.

Enough conjecture on my part, below is the published info:



DTC Advanced Diagnostics: U0100

DTC U0100: F-CAN Malfunction (PCM-TCM)


General Description

The controller area network (CAN) transmits/receives pulsing signals to/from the control modules simultaneously by using two signal lines (F-CAN A_H and F-CAN A_L). If the transmission control module (TCM) cannot receive the signal sent from the powertrain control module (PCM) for a specified time, or if the received signal is abnormal for a specified duration, the TCM detects a malfunction and stores a DTC.



Monitor Execution, Sequence, Duration, DTC Type

Execution	Continuous
Sequence	None
Duration	1 second or more
DTC Type	One drive cycle, MIL on, A/T gear position indicator blinks

Enable Conditions

Condition	Minimum	Maximum
12 volt battery voltage	9 V	16 V
Vehicle	ON mode

Malfunction Threshold

Either of the conditions is met:

The TCM cannot receive the signal sent from the PCM at least 3 times.

The TCM receives abnormal signal from the PCM for at least 1 second.

Possible Cause

NOTE: The causes shown may not be a complete list of all potential problems, and it is possible that there may be other causes.

F-CAN circuit F-CAN A_H line open

F-CAN circuit F-CAN A_L line open

PCM internal failure

TCM internal failure

Diagnosis Details

Conditions for setting the DTC

When a malfunction is detected, the A/T gear position indicator blinks, the MIL comes on, and a Pending DTC, a Confirmed DTC, and the freeze data are stored in the TCM memory.



Conditions for clearing the DTC

The A/T gear position indicator comes off by turning the vehicle to the OFF (LOCK) mode. The MIL is cleared if the malfunction does not return in three consecutive trips in which the diagnostic runs. The MIL, the Pending DTC, the Confirmed DTC, and the freeze data can be cleared with the scan tool Clear command.

 

Some info on U100 - it appears this code is generally a "communication lost" code, and I can see multiple variants of it in the service literature. It seems like multiple modules can report the code, so the code itself is more useful when the reporting module is known. You mentioned PCM-TCM, so I assume one or both of them reported that code.

I'm guessing that data for the blind spot system and emissions control are on the same network, so loss of communication would set those lights.

Enough conjecture on my part, below is the published info:



DTC Advanced Diagnostics: U0100

DTC U0100: F-CAN Malfunction (PCM-TCM)


General Description

View attachment 471512

The controller area network (CAN) transmits/receives pulsing signals to/from the control modules simultaneously by using two signal lines (F-CAN A_H and F-CAN A_L). If the transmission control module (TCM) cannot receive the signal sent from the powertrain control module (PCM) for a specified time, or if the received signal is abnormal for a specified duration, the TCM detects a malfunction and stores a DTC.



Monitor Execution, Sequence, Duration, DTC Type

Execution	Continuous
Sequence	None
Duration	1 second or more
DTC Type	One drive cycle, MIL on, A/T gear position indicator blinks

Enable Conditions

Condition	Minimum	Maximum
12 volt battery voltage	9 V	16 V
Vehicle	ON mode

Malfunction Threshold

Either of the conditions is met:

The TCM cannot receive the signal sent from the PCM at least 3 times.

The TCM receives abnormal signal from the PCM for at least 1 second.

Possible Cause

NOTE: The causes shown may not be a complete list of all potential problems, and it is possible that there may be other causes.

F-CAN circuit F-CAN A_H line open

F-CAN circuit F-CAN A_L line open

PCM internal failure

TCM internal failure

Diagnosis Details

Conditions for setting the DTC

When a malfunction is detected, the A/T gear position indicator blinks, the MIL comes on, and a Pending DTC, a Confirmed DTC, and the freeze data are stored in the TCM memory.



Conditions for clearing the DTC

The A/T gear position indicator comes off by turning the vehicle to the OFF (LOCK) mode. The MIL is cleared if the malfunction does not return in three consecutive trips in which the diagnostic runs. The MIL, the Pending DTC, the Confirmed DTC, and the freeze data can be cleared with the scan tool Clear command.



View attachment 471513

Thank you very very much.
I truly appreciate this info.

 

Remember when vehicles were not smartphones? Pepperidge Farm remembers...

 

Let's just say that regardless of whatever the dealership says on the day I get my truck back.....I am not going to trust it to be reliable until it has proven itself to be so.

I just upgraded to the max AAA membership since I tow my boat locally......and travel in general to SC, coastal GA, and FL all the time.

I now have AAA Premier RV coverage.......they will tow my truck 200 miles.....and cover 500 bucks of expense to tow my boat.....there is also 1500 of travel interruption coverage.

 

Just in case you are like me and do not know what things cost these days.....I just called 2 random companies to get some "sample" towing prices.

Not Cheap!!!!!!

This info is regarding local towing in my county just outside of Atlanta.

Company A- to tow my truck- $175 hook up fee and $3.50 per mile
could not get boat tow info from them.

Company B- to tow my truck- $95 dollar hook up fee and $4.00 per mile
to tow the boat if my truck is broken...285 hook up fee and $5.00 per mile.

Note 1- hook up does not always mean hook up......but to physically transport the vehicle/boat.

Note 2- I did not talk with anyone about 75/100/150/200 mile tows so I have no info about that sort of situation.

 

Here is the update.....hopefully the truck will be reliable again.

I am going to drive it around town during this week but I'll be taking our Toyota Camry to Florida on Saturday for a week.

Then I'll be able to drive the Ridgeline around town the following week to verify it is reliable..... Because the following week I'm taking a trip to Myrtle Beach.

Each day I will do a cold start in my garage and pull the truck out and drive about 20 or 25 miles in the morning.

I will park it and probably while it's still warm I'll fire it back up and go up and down the road again.

I should be able to get between 6 and 10 of these driving scenarios done before I go to Myrtle Beach.

The root cause was connector 318 had a loose pin set.

My opinion is that the vendor manufactured the harness and all the pins were placed in the cavities and inserted...... However it seems like at least one of the pins did not latch and over time backed out just enough to provide an unstable connection.

When the hard fault occurred during the dealer test drive it set all kinds of additional codes that weren't even present on the very first day.

I'm very glad it failed in a hard and permanent manner and that allowed them to do proper troubleshooting.

Here are two pictures of my documentation.

 

@BeshmoHandes

Can you please post info on C318?

Location of the connector........pin info like numbers/position/wire colors.

Schematic with the connector in it.

Thank you in advance for looking up the info.

In my prior life I had 100 percent access to 2 different OEM resources.....I miss that!

 

@BeshmoHandes

Can you please post info on C318?

Sure! C318 is an inline connector between the TCM pins 34 (F-CAN High), 47 (F-CAN Low) and the rest of the F-CAN network. C318 is a two pin connector. Pin 1 is CAN High, pin 2 is CAN Low. The wire color changes from the male to the female mating connector.

Oddly, AutoRepairSource is not showing schematics for me today, so I had to switch to Chilton - which means this data is from 2020, but is almost certinaly the same for 2023 models.

The other mentioned connectors all have F-CAN as well.

C310

C311

TCM Connector

Terminal No	Wire Color	Terminal Name
1	BLK	GND1
2	BRN	GND2
3	LT_BLU	VBSOL
5	RED	+B
6	GRN	VBSOL2
7	BLK	F-CAN B_H
8	GRN	SG1
9	YEL	ESL_PWR
10	GRY	VCC1
12	BLU	TATFP
13	GRN	PARKSEN1
15	BLU	PARKSEN2
17	PUR	VCC2
19	BLK	PCL
20	PUR	F-CAN B_L
28	PNK	SDNP
29	TAN	SUPP
30	BRN	TATFM
31	WHT	NM
32	YEL	PARKOUT
34	LT_BLU	F-CAN A_H
35	LT_GRN	SHC
36	BRN	SHB
37	BLU	RVSOUT
38	YEL	SHA
39	LT_BLU	LSE
40	WHT	LSC
43	RED/BLU	NOUT
47	WHT	F-CAN A_L
51	PNK	SHD
52	TAN	PLA
53	PUR	LSD
54	BLU	LSA
55	RED	LSB
56	GRN	IGN_TRX
58	BRN	IG1

This portion of the F-CAN network shows Connectors C310,C311, and C318:

And for good measure, the SBW connector (20P):

 

I am glad they found the source of the issue, just a loose wire causing network/com issues. You probably does not need it, but you may want to know the location of the connectors that you could reset, if the same issue returns.

If it is my RL, I wouldn't worry about it after the fix. The chances are that it won't return and if it does, let them fix the issue again and trade my RL in for a new one...

 

Hope it's fixed! A friend had a Super Duty Ford that lit up like a Christmas tree one day after a rain. He took a video of it, but the service manager wouldn't watch it. They "couldn't replicate" the problem so he was sent home. He searched various Ford forums and found this was happening quite a lot on other trucks. The main wiring harness that passed through the firewall didn't have waterproof plugs and shorted out when it was wet. He dried it out and put dielectric grease on it and traded it in on a Chevy.

 

Good for you ATL. They actually diagnosed and fixed based upon their diagnosis. Hope they got it right and your were smart to take it there while it was happening and best of all so far it seems like you have a dealer that cares. Sounds like it would have been a good candidate for a SMA video. I didn't think dealers were capable of this type of fix these days, good news. If no more limp modes when you get back, should be good to go.