RangeRovers.net Forum banner

1 - 10 of 10 Posts

·
Registered
Joined
·
1,444 Posts
Discussion Starter #1
Hello, all.
The Body Control Unit functions of my 2003 FFRR has been acting up for a while now, and I've been checking ground points and connections where I can, with no luck.
The problems have been things like various buses not working, the doors not always automatically locking at xx MPH, odd gremlins like that. I have a hard time accessing/interfacing with the light control module and a few other subsystems with my RSW AllComms too.
I recently looked for a problem between the alternator and ground (or power side, for that matter), and looking at RAVE, came across an in-line diode between the alternator connector C0053 and the F5 fuse. Looking for that took me into the plastic left fuel injector wire "loom" cover. I found the diode in there, in-line. I found the molded potting around the actual diode crumbling to pieces. I'll try to attach the pic here....
 

·
Registered
Joined
·
1,444 Posts
Discussion Starter #2
Okay, so much for adding the jpeg, the site won't even let me edit my post currently, so here's my "reply" to myself to expand on the problem and my question...
The ceramic molding around this diode is crumbling, but I did capture a part number on the body before it disintegrated:
"BMW 1251 7505886-01" is clearly printed, with a "537812 10" printed below that.
I've searched all over the web for anything that corresponds to those numbers with no luck.
I also searched for the reference out of the RAVE schematic, "G126". No luck there either, other than one English reference to it that went nowhere in a post, and a reference to it in a german post that did not appear to follow with any part numbers.

Does anyone out there know what that diode is as far as capacity/size or any specs, and/or where I can find a suitable if not exact replacement?

I'd hate to think that Land Rover or BMW intended for the entire engine cable harness to be replaced when this diode between the alternator and the F5 fuse (then onward to the ignition switch) fails or degrades. A diode is extremely cheaper than and easier to replace than the cable harness.
Any ideas or general info on this diode?

Thanks.
 

·
Registered
2002-2005 Range Rover MkIII / L322
Joined
·
346 Posts
Can you post a picture? I have a wiring harness here in my basement from a 2004. If you post a picture I can look at my harness and try to find it. If I do have it and it is not terribly destructive and large I could mail it to you.

I know others on the forum have plenty of spares - so if you have a picture you may have more luck. Contact the site admin if you have issues.
 

·
Administrator
Joined
·
27,820 Posts
Pictures issues have been solved... no need to contact me, admin or a mod. :lol:

Although I am intrigued by this burried diode designed by of all companies...BMW.

So kg, what kind of Rover do you have? You still haven't put that in your signature yet. :mrgreen:
 

·
Registered
2002-2005 Range Rover MkIII / L322
Joined
·
346 Posts
I have updated my profile to reflect my ownership of a 2004 Range Rover.

I just transferred the plastic box for the injector loom over from my spare to my Rover as the plastic that holds the 8th cylinder injector connector was broken. Not an easy task as each injector connector needs to be removed or the loom cannot come out. I used a bobby pin with cut tips to accomplish this as I do not own one of the special wiring harness tools.

Back on point - I think I know what the OP is looking for but would like to confirm with a photo before I start unraveling the loom. I thought, what apparently is a diode, to be some sort of wire connector. It would make sense so that signals go only one way.
 

·
Registered
Joined
·
1,444 Posts
Discussion Starter #6
I'll try to upload the pic again with this response. It's 2.7 meg, so not too big. The attachment window allows me to select the JPG, and with it selected I click the UPLOAD button, but nothing seems to happen... Or maybe I just can't tell until I close the response.
 

Attachments

·
Registered
Joined
·
1,444 Posts
Discussion Starter #7
Thanks RRToadhall - You fixed my upload problem.
And that's for the reply, KG74.
This pic was taken before I moved it, at which time the ceramic around the diode crumbled to pieces.
It's hard to believe that an aftermarket replacement wouldn't be available. A new harness is around $2400, and a used harness might not be in much better shape. So just replacing the diode should be the repair from the manufacturer's life cycle repair plan.

It's sad to think that a small and otherwise easily replaced part like this could fail, and influence the owner to get rid of the RR, and never want another one as a result.
 

·
Registered
2002-2005 Range Rover MkIII / L322
Joined
·
346 Posts
Send me a pm with your mailing address. I will send you a picture of what I have and if it is good I will throw it in the mail. Tell me how much wire you are going to want. One side is easy the other seems to go deep into the loom
 

·
Registered
Joined
·
1,444 Posts
Discussion Starter #9
Thanks, KG74.
If it's the same one, about 4 inches of wire on both sides would be plenty for me to splice it in place.
If you can post a pic to make sure it's the same one, if you're not sure from the location and description.
I sent a PM with my mailing address.
I appreciate the help.
 

·
Registered
2002-2005 Range Rover MkIII / L322
Joined
·
346 Posts
I sent you an email with a picture of what I have and its condition. Tell me if it will work and I will get it in the mail.
 
1 - 10 of 10 Posts
Top