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Discussion Starter #1
Hey all, I know this is a classic 9000 issue, but if they still work SOME of the time is there a sensor I can clean? or a relay I can replace? or ANYTHING I can do to coax them back to regularity?
 

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Usually bad solder joints on the module. It can be reflowed with hot air or and iron and plenty of flux.

With hot air, be careful because the PCB doesn't tolerate high temperatures well.
 

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So talk me thru this a bit..if you would? I'd really like to get these back full time.
 

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Unclip the box from underneath the steering column and remove the wiring harness.

Then slide open the box by prying some tabs.

How good are you with soldering?
 

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Discussion Starter #7
Unclip the box from underneath the steering column and remove the wiring harness.

Then slide open the box by prying some tabs.

How good are you with soldering?
I own a soldering gun and a reel of solder....that is the extent of my soldering experience, lol...not what I want to practice on buuuut....
 

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You'll need an iron designed for fine work. If it has a trigger, forget it.

Hot air rework is less risky. Sub $100 stations are available on Amazon.
 

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So talk me thru this a bit..if you would? I'd really like to get these back full time.

The control module for the central locking system is under the dash - way over on the left hand side.

To access it, drop the fabric covered panel that is above the gas/brake/clutch pedals. Look way over - almost to the wall - and up. You will see a rectangular black box held in place with a u-shaped spring clip. Pull the clip and release the module:



Disconnect the module from the harness and bring it to the bench.

Open the cover and inspect the solder joints. Specifically at the interface of the harness pins to the PC board. These soldered joints are almost always the problem.

While admittedly not having done this repair that many times - maybe 5 or 6 - I believe I have had a 100% success rate just by reflowing these soldered joints:



I've never had to go up into the PC board.

I didn't have to because there were obvious cracks where the external connector pins interfaced with the board. Use a magnifying glass and they will jump right out at you.

Use a clean 25-40W soldering iron (pencil tip). I keep a bent tip on hand for working on the bench. It makes things a bit easier but isn't necessary:



Use just enough solder to tin the tip. No additional solder is required to reflow the joint - and adding more solder will often cause bridging (see below).

There are 6 connections. Do each, one by one. Only touch each the tip to the interface long enough to melt the solder.

Watch the surface, when the solder changes color from dull to shiny it's re-flowed. Remove the heat and move on to another joint - preferably one not close to the one you just did. Also listen carefully while applying the heat. When a previously soldered joint re-flows it will emit a tiny squeak sound. As above, stop and move to another joint.

The area will get HOT. Give the board time to cool off between re-flows. Some of the nearby components are heat sensitive and overheating will damage them. Also it will prevent you from burning your fingertips.


Important: Be careful of bridging - causing a connection from one joint to the adjacent one. If this does occur, run the blade of a utility knife between the bridged joints to remove the excess solder.
 
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