Y Cable Replacement Tips?

bcislander

'07 Mercedes-badged Dodge
I plan on replacing the 'infamous' Y Cable in my Sprinter sometime in the very near future. I had a quick look around & under the van to see what potential 'snags' there might be.

The main difficulty I saw was accessing the alternator connection post. I couldn't see it from above, or below. The only useful thing I was able to find from a Forum Search is that the nut is 13mm.

Does anyone have any tips/tricks that may be of use to make it easier to remove & replace the cable from the alternator?
 

smiller

2008 View J (2007 NCV3 3500)
Go at the alternator cable nut from below, it's a blind job but not that difficult to get at (make sure that you disconnect the battery first so you don't inadvertently test the fusible link! :eek:) Sometimes there is a plastic cap over the stud and if so it just snaps on and off.
 

lindenengineering

Well-known member
Just to add !
Have a bag of zip ties on hand--useful and some areas of the cable running up to the battery that which often needs clipping up to prevent sag and rub against other components .
Dennis
 

bcislander

'07 Mercedes-badged Dodge
Go at the alternator cable nut from below, it's a blind job but not that difficult to get at (make sure that you disconnect the battery first so you don't inadvertently test the fusible link! :eek:) Sometimes there is a plastic cap over the stud and if so it just snaps on and off.
Yes, :thumbup: I had already decided to use the battery disconnect & start at the battery end of the cable. Previous experience with live wires & screwdrivers :censored:
Thanks for the plastic cap 'warning'.
 

bcislander

'07 Mercedes-badged Dodge
Mission accomplished! :thumbup:

Took me about 2h, as I expected. Thanks to the advice about the plastic cap on the alternator connection, the only real 'gotcha' was the extra attachment point to the transmission housing (not on the original cable), which required a bolt that I had to look for in my 'spare stuff bin'.

The original cable didn't look too bad at the starter 'junction' point, but there was a noticeable increase in the voltage after installing the replacement.

Once again, thanks to all.
 

VanGuy6678

Member
I'm relatively new to the Sprinter mechanicals. Why is the Y Cable "infamous?" What year model did you replace this on? Thx!
 

showkey

Well-known member
I'm relatively new to the Sprinter mechanicals. Why is the Y Cable "infamous?" What year model did you replace this on? Thx!

A known problem that causes lower than normal voltage to the truck electrical system and components.
The root cause is corrosion or poor connections causing higher than normal resistance. Electrical resistance causes voltage drop in the cable.

One indication is less than 13.8-14 volts on a the scan gauge while driving.

Other indicators are some unexplained engine or body codes. Weird gauge or light function.
Low battery charge.
 

VanGuy6678

Member
A known problem that causes lower than normal voltage to the truck electrical system and components.
The root cause is corrosion or poor connections causing higher than normal resistance. Electrical resistance causes voltage drop in the cable.

One indication is less than 13.8-14 volts on a the scan gauge while driving.

Other indicators are some unexplained engine or body codes. Weird gauge or light function.
Low battery charge.
Given all the high quality, marine-grade wire I'm running in my 2010 build, and the 120 amp battery-to-battery charger, I sure don't want a weak link in the Y-cable. What are you using as a replacement/how is it better? Cost for materials? Any recommended resources? Sounds like a great proactive project. Thanks!!
 

showkey

Well-known member
It is not clear if the factory cable has been upgraded or changed ? I think the part # has not changed ??????
There have been write ups by members making their own upgraded cables. Care and safety is critical because there is basicly unlimited current flow potential if the cable is shorted due to chaffing, routing or over heating.

It is an issue to be aware of ....but ....not every truck has the issue.
 

bcislander

'07 Mercedes-badged Dodge
I'm relatively new to the Sprinter mechanicals. Why is the Y Cable "infamous?" What year model did you replace this on? Thx!
The 'infamous' nature of the Y-Cable has already been explained.

The year/model info is in my 'signature', a 2007 NCV3.
 

bcislander

'07 Mercedes-badged Dodge
It is not clear if the factory cable has been upgraded or changed ? I think the part # has not changed ??????
There have been write ups by members making their own upgraded cables. Care and safety is critical because there is basicly unlimited current flow potential if the cable is shorted due to chaffing, routing or over heating.

It is an issue to be aware of ....but ....not every truck has the issue.
The part # has changed.

The tag on the original cable, part # A906 440 35 38
New cable, part # A906 440 16 41

Here's hoping the new design lasts longer.

Yes, there is the potential for very high current flow, if the cable shorts somewhere between the battery +'ve terminal and the cable in-line fuse situated between the alternator & the starter. There is no fuse in that portion of the cable.
 

smiller

2008 View J (2007 NCV3 3500)
I'm not certain there's really a need for a custom Y cable replacement, or at least I'm not convinced yet. The Y cable failed on my 2007 (system voltage about a volt low, spurious codes occasionally set during engine start) and a new cable restored normal system voltage (approx. 14.1 volts) and completely eliminated the code-throwing problem. The replacement cable had improved crimps over the original, and the Y crimp terminal (at the starter) was more substantial. Plus I'm not sure I could have built the harness myself for the cost of an OEM replacement (about $70 online, but $130 at the dealer).

My attitude is wait-and-see... I expect that the new cable will be a permanent fix but if not then I'll go the custom route.
 

VanGuy6678

Member
Wow, where do you find a new OEM cable online for $70? Best I've found is $92 so far. And which scangauge model do you recommend? I'd like to monitor system voltage regularly. Thx.
 

showkey

Well-known member
I see Europarts says in their part description the part has been revised 4 times with the prior part discontinued.

"If you have had continuing sluggish starts and other electrical problems and you have a good alternator, generating an output of over 14V, you may look closely at your positive battery cable. This is often an area of electrical trouble.
This is the fourth revision of this cable by Mercedes. All three of the previous units have been discontinued."

http://europarts-sd.com/item.asp?cID=109&PID=2398
 
Last edited:

VanGuy6678

Member
I'd love to know which "revision" I have in my 2010 MB. Anyone happen to know which versions of this cable appeared in which year vehicles?
 

bcislander

'07 Mercedes-badged Dodge
I'd love to know which "revision" I have in my 2010 MB. Anyone happen to know which versions of this cable appeared in which year vehicles?
You can probably find out the part # by looking in the battery compartment. The tag with the cable part # is usually fastened to the cable near the battery terminal end. This may give you an 'educated guess' as to which revision of the cable you have installed.
 

Top Bottom