MY06LX EWD needed badly (1 Viewer)

[PADDO]

It’s worth the effort to fix. I’ll bet an old exhaust leak had something to do with the initial problem.

 

[goldigital]

Intersteting comment PADDO ... would never suspect that but you’re right very possible.
The actual BG1 is sitting above and about 6” away to the left of mufler. On the picture above I had pull down the bunch to work on it, so in reality is not that close. Either way, my initial thought was someone pointed a torch at it, crazy thought i know, but BG1 was melted like a candle!

Cheers! and good weekend!

 

[theophilus]

This thread was the key to me finding my issue! So thankful for your tenacity in finding your issue, as well as PADDOs comment about the muffler leak. I had a muffler hole that was left a while (ostensibly because it sounded throaty). My theory is that sitting idling with a muffler hole/exhaust leak lets the hot exhaust wreak havoc on the wiring under our rigs. Hot air rises and finds the worst possible place to escape (top of frame rail), and is the destroyer of wires and BG1. Here's a pic of my C1721 short, directly above the frame rail, right next to the middle muffler where I had the hole. I'd call that a short, wouldn't you? (side note: amazing design that anything in the suspension ECU works at all with a short like this connected to it).
It feels like a Public Service Announcement for AHC folks "if you have a muffler leak, FIX IT before it's the size of a softball and melts your AHC wires down)

 

[PADDO]

You’re the fourth of fifth case of exhaust gases damaging the systems wiring loom that I’m aware of. Sage advice: if you’re experiencing C1721/23 faults or intermittent damping issues then it’s prudent to thoroughly inspect for burnt wiring due to exhaust system leaks.

 

[theophilus]

Fixed! C1721 is finally gone! Here's another shot of the fried wire, and a link to the silicon high temp wires I used to splice the harness.

https://www.amazon.com/BNTECHGO-Sil...coding=UTF8&psc=1&refRID=JZ47F6B6DXQ6H72HEBPM

 

[Stricmic000]

Wow, is this type of damage possible without throwing any dct but causing malfunction?

 

[Stricmic000]

My issue is both rear damping actuators fail to function in L and N modes but work correctly in H, would it stand to reason that I have an issue between b12 bf5 id6 and the ECU? because if it was a bg1 bd1 or b13 issue they wouldn't work at all?

 

[Rubibu]

This thread was the key to me finding my issue! So thankful for your tenacity in finding your issue, as well as PADDOs comment about the muffler leak. I had a muffler hole that was left a while (ostensibly because it sounded throaty). My theory is that sitting idling with a muffler hole/exhaust leak lets the hot exhaust wreak havoc on the wiring under our rigs. Hot air rises and finds the worst possible place to escape (top of frame rail), and is the destroyer of wires and BG1. Here's a pic of my C1721 short, directly above the frame rail, right next to the middle muffler where I had the hole. I'd call that a short, wouldn't you? (side note: amazing design that anything in the suspension ECU works at all with a short like this connected to it).
It feels like a Public Service Announcement for AHC folks "if you have a muffler leak, FIX IT before it's the size of a softball and melts your AHC wires down)
View attachment 1893586

Theophilus, have you been able to get to the burnt cabeling and do the splicing even without cutting the fender like goldigital did? Seems as indicated today on Techstream, my AHC besides having too high pressures front and rear has the C1721/C1723 codes too after I was having a split open muffler.

 

[theophilus]

Theophilus, have you been able to get to the burnt cabeling and do the splicing even without cutting the fender like goldigital did? Seems as indicated today on Techstream, my AHC besides having too high pressures front and rear has the C1721/C1723 codes too after I was having a split open muffler.

It just depends on where the wires are burnt.

If you put your hand up on top of the frame rail you'll probably feel the crispy remnants...My wires were burnt a little further forward, just forward of the rear wheel, right at the back of the muffler. If your leak is further back - say in the pipe as it climbs over the rear axle, there's a set of connectors sitting on top of the passenger frame rail that are nuts to reach, and I totally understand why someone might decide to chop some stuff to get there.

Hope that helps someone.

 

[Rubibu]

I risked doing the repair yesterday in the afternoon or better say it turned morning while doing so... I think Theophilus was one of the more lucky guys as his wires were much more accessible.

My wires were partially burnt forward of the wheel well but also on top of the frame rail. Both connectors melted and so did some wire insulation. Most of the wiring insulation was intact but the corrugated tubes that should protect the cabeling were pretty much caked beyond recognition, some spots even behind the conectors and wheel well. The connectors look very much the same like the already shown...

Nevertheless I was happy to discover that the ABS Sensor cable for the passenger side rear wheel which is running in the same tube was intact.

I ended up cutting the connectors and pulling the wires backwards (unclipping the retainers that fasten the corrugated tube to the frame and disconnecting the ABS connector) untill the whole strand was hanging between the spare wheel and axle.

I then did all the carefull cleaning, splicing, wrapping and fitted a new tube. Afterwards I slid the cables back into position, I reconnected the ABS and did the splicing up front.

It might have helped that I got a hand made exhaust which is shorter and takes less space in general. Otherwise it would have been a pretty tight operation.

I finally fitted another piece of tube around the wiring for protection and ziptied to the frame.


After deleting the AHC codes by use of techstream, I took her out for a test ride. All the little bumping is gone and the ride is very smooth again. I have been super nervous about this repair and tried to skip it day by day because of the installation situation but I couldn't be happier now.
I am going to change the rear springs and get all pressures within spec soon... curious to see how well the system can be fine tuned


Thanks a LOT to Paddo, goldigital and theophilus !!! I very much appretiate your write-ups.

Ruben

 

[Moridinbg]

Don't stare at photos of books, like some kind of a cavemen. The electronic FSM is super convenient, just make sure to browse the EWD through the supplement - GSIC - Global Service Information Center - https://lc100e.github.io/pdf/ewd/em0020e/htmlweb/index.html
This is the schematic for the body harnesses, which is both the harnesses inside the cabin and on top of the chassis - GSIC - Global Service Information Center - https://lc100e.github.io/pdf/ewd/em0020e/htmlweb/index.html

Here is the complete wire harness schematic in one image

The BI1/2/3 & BD1/2 which seem to be the worst offenders

I hate the guy that decided on this routing and the connector locations. I hate him deeply and passionately.

 

[Scrappy]

Adding my experience here as testament to Paddo's astute advice to check for melted wires due to the exhaust if you have code C1721 or C1723. While I did not have an exhaust leak, the harness that runs across the rear frame of the rail connecting BG1/2 and BD1/2 had a rusted bracket that snapped off, so the line was sagging and sat about a quarter inch from the exhaust pipe. So another case of exhaust heat source melting these wires.

 

[Scrappy]

Fixed! C1721 is finally gone! Here's another shot of the fried wire, and a link to the silicon high temp wires I used to splice the harness.

https://www.amazon.com/BNTECHGO-Sil...coding=UTF8&psc=1&refRID=JZ47F6B6DXQ6H72HEBPM

View attachment 1895823

Did you use 18 gauge to splice?