New diagnostic connector cap - doesn't stay on

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db9
Posts: 100
Joined: Jun 30, 2019 8:27 AM
Location: Mississauga, Ontario

New diagnostic connector cap - doesn't stay on

Post by db9 »

Thanks to all for answering questions.. this is bit of a dumb one..
As part of cleaning things up under the hood I picked up a replacement plug cover (15 pin D shape) (BMW part 12521286052) problem is the cap won't stay on the connector ? is there something missing like a clip? the cover is a "larger" D than the connector body

Car is 84 533i Auto (02/84 build)
dsmith
Posts: 2361
Joined: Jan 20, 2012 12:52 AM
Location: Charleston, SC

Re: New diagnostic connector cap - doesn't stay on

Post by dsmith »

I have had that and put a tiny dab of black rtv on the cap, let dry and it gives a little friction to hold down.
vinceg101
Posts: 4561
Joined: Jun 20, 2007 2:40 AM
Location: Los Angeles, CA

Re: New diagnostic connector cap - doesn't stay on

Post by vinceg101 »

I had/have luck with putting one layer of electrical tape around the bottom lip (black or red depending on your flavor). Works like a charm.
Federico
Posts: 462
Joined: Sep 16, 2013 6:38 PM
Location: Argentina / California

Re: New diagnostic connector cap - doesn't stay on

Post by Federico »

IIRC, there should be a couple tiny teeth or protrusions on the flat side of the plug, which hold the cap down.
Mine are broken off letting the cap free, probably the same issue everyone is having.
It might be possible to glue on some bits of plastic to the plug and make it work.
Federico
Posts: 462
Joined: Sep 16, 2013 6:38 PM
Location: Argentina / California

Re: New diagnostic connector cap - doesn't stay on

Post by Federico »

Here's a pic of those little suckers:

Image

10 Bucks ain't too bad:

https://www.ecstuning.com/b-genuine-bmw ... 521273100/
Federico
Posts: 462
Joined: Sep 16, 2013 6:38 PM
Location: Argentina / California

Re: New diagnostic connector cap - doesn't stay on

Post by Federico »

So, today I went ahead and replaced the diagnostic plug on my 528i

The round terminals have double tabs, like so:

Image

So, I made myself a little tool using a round brass terminal. It was just slightly too large in diameter and I used a dremel cutting wheel to widen the "gap" and be able to close the cylinder until it fit the plug nicely. I also sharpened it so that it would slide over the terminal to be removed.

Image

Once set in place, a small screwdriver was used to push the terminal out the bottom.

Image

It's a done deal:

Image

Image

Made myself a schematic just in case :laugh:

Image
Federico
Posts: 462
Joined: Sep 16, 2013 6:38 PM
Location: Argentina / California

Re: New diagnostic connector cap - doesn't stay on

Post by Federico »

I do notice that with a new plug and cap, the latter doesn't really want to come off.

I'm thinking about shaving some plastic off, so that the tabs bend inwards when pulling on the cap, instead of them locking in place. I don't want them to break again.
JohnH
Posts: 676
Joined: Jan 24, 2007 9:55 AM
Location: Surrey,UK

Re: New diagnostic connector cap - doesn't stay on

Post by JohnH »

Federico wrote:I do notice that with a new plug and cap, the latter doesn't really want to come off.
You could just break those locking tabs off :laugh:

Excellent work Federico. I really like the ejector.
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