I have an intermittent 1095 ABS error message. Which the forum search feature is telling me is going to require some light soldering of the incoming power pins on the ABS module circuit board. I'm a complete novice at circuit board repair, having never soldered one.

I doubt my heavy duty soldering gun is appropriate in this case. What is the best tool for this job ? Something low powered I'm guessing. Any specific recommendations on make and model of soldering tool would be appreciated. What is the correct or best type of solder ?

Do I need to rig some kind of heat sink ? I'm concerned that any prolonged heat is going to ruin the circuit board.

thanks,

Z.

 

Hi Z, I've never been in the abs module, but will be happy to help get things rolling for you.

Desoldering braid: if you can, pick this up. It's a $1 item, typically a 1/8th inch tall, 1mm thick piece of braided copper. To get old component out, place this right on top of the solder joint. Put hot soldering iron on top. As copper heats, it melts old solder, this actually sucks all of the old molten solder out into the copper braid. Just lift up (by now the old molten solder is solid), cut the end of the braid off, lift soldered component out.

Solder: it must be electrical solder. Typically it will contain rosin. Radio shack rosin solder will do the job just fine.

Rosin: do take the time to purchase rosin separately too. I know you know this but dont mix up plumbing rosin(or solder) and electric rosin or solder. Rosin is a gelatinous substance, almost as thick as petroleum jelly. Apply it to the connection/connector prior to heat. As it heats it will burn off ( its non conductive) cleaning oils, oxidation, things that would interfere with the solder joint. I typically dip the end of my solder wire into the rosin as i bring it over to solder the joint. You'll be amazed at how this allows the solder to melt and flow so easily.

Worried about too much heat? Use a heat sink. These are what looks like a tiny spring loaded flat clamp. Spring allows the blunt pincers to meet and stay closed. You would attach it to the capacitors lead. I dont think its necessary. Btw, any sort of metal slug will work. The soldering iron will not be on the joint long enough to cause damage, especially if you use rosin.

The setup, and access to, the circuit board/capacitor will dictate the best soldering iron to use. Someone wh has worked on this board one it can jump in here to advise us.

A larger (how many watts/how much heat energy is available) soldering gun will make one think, maybe it will burn things or damage something. Not true. Youd be surprised at how much faster a 35watt soldering gun will heat a lead to soldier's melting point than the smaller 10 watt unit. This leads to the fact that the size and shape of the soldering iron or gun's tip is most important for this job. Do you need to target a joint that's deep, or close to other components? Go for a needle nose soldering iron. All else being equal I've had great results with the radio shack dual position (two trigger positions medium and high) heavy duty soldering gun. It also has a built in flashlight.

Ready to do the job?

Wad up a paper napkin, wet it with water. Wring it out. Place it to the side. Heat up soldering iron. After a bit touch the solder to the tip. Does it melt right away? If so great, now "tin" the tip. Rub the tip across the wet paper wad, it will capture oxidized dirt. You'll see the tip looks cleaner. Now touch the solder to the tip, allow it to melt covering the tip. You dont want any solder splash so wipe excess off on the wet napkin. Tip will still be shiny with solder.

Dip the end of solder in the rosin. Paint the rosin on the surface you will be soldering (circuit board). Coat end of capacitor's lead. Now tin the end of the capacitors lead. Touch the hot soldering iron to the metal lead just above where you want the solder deposited. Simultaneously touch the solder to the spot you want to tin. Let the hot lead itself melt the solder. This way the iron brings the metal lead up to temperature- it will melt the solder. If you were to say put the soldering iron on the lead in between the solder and the lead, the solder will melt but you may not have the lead hot enough for a good connection. This can result in what is called a cold solder joint = bad (sometimes intermittent) connection.

Now thread the capacitors lead through hole in circuit board. No hole? Ok, lay the lead flat on the circuit trace (rosins already there right?) Place the soldering iron on the lead. (Always heat the conductor, not the solder) since it's already tinned, you'll see the solder flow. If you need a bit more solder, assist with your roll of solder.

**should have mentioned earlier- electrical solder comes in different thicknesses. Scope out the job befor you buy solder. If you cant, Buy the thinner one if your choosing. Easy as pie to twist two or more strands of thin solder together if you need thick***

Z, dont fall into the trap of thinking that solder will secure a component (its melted metal right? :-) it can vibrate lose). Its just for the electrical connection. Secure components and connectors mechanically.

After solder flows and connection done LEAVE IT ALONE /walk away for a minute or two. Someone way smarter than me, who worked with special US Navy equipment taught me this. Yea probably overkill for this job, but best to just do it right.

Hope this helps.

John

 

Excellent tutorial. The only thing I would be unclear on is the bit where you say "Secure components and connectors mechanically". Are you talking about the little bits just soldered or the board or something else? If its the board that obviously bolts/screws but if its the component you just soldered?

 

Frankc, great question. It was late, I was trying to cover a lot. I got caught up in trying to make a point but just confused things. There was probably no need for me to add that statement here mate. Sometimes folks, myself included over the years, default to thinking that soldering is kind of like welding strength wise in that you are joining 2 pieces of metal with melted metal. Of course soldering an electrical connection has nothing to do with welding.

Threading a component's lead through a circuit board's hole gives you more than enough of a mechanical connection. I probably should have just said use a wire tie or a dab of glue to secure a component if its subject to vibration. If you're joining 2 wires end to end, secure the connection with shrink wrap or electrical tape, that kind of thing.

Soldering a component to a circuit board should be fine. Sorry for the over cautious warning and thanks for pointing it out.

John

 

Great write up John! The only thing I would add is to purchase a solder sucker and watch a video on YouTube on how to use it... I had to replace a relay and a capacitor on my refrigerator's main board (since the condenser fan wouldn't come on) and that solder sucker tool was AWESOME in removing the old solder around the pins! I also used my old Craftsman soldering gun and with the proper use of the solder sucker I didn't have any problem with excess heat as it was so quick on removing the old solder.

 

would either of these be a good choice ? All the ones I'm finding on Amazon are no inexpensive , I'm concerned the quality is not there.....

( No Radio Shack in my area anymore )

Z

 

Thanks Chris and Frank. Hey you know I was thinking. Everytime we instruct someone about how to work inside the door, regardless of how obvious it seems, we always are sure to say: Disconnect the battery for safety, you could lose a finger. That never gets old.

In that spirit: For anyone soldering, Be sure to wear eye protection! Solder can and often does "pop" and goes airborne or leads bent under tension unspring with molten solder on them . No one needs 600 degrees of molten metal in their eye.

John

 

Z - either of those would work as long as it is a pencil tip soldering iron

use solder that is 37%lead, 63%tin - this has the best characteristics when soldering electronics

when soldering - don't blob the solder on - should have a nice concave fillet, should be nice and shiny when done - dull and grey are cold solder joints which cause problems

Too much heat can lift the pads/circuit runs off of a circuit board as well as damage/destroy IC's - this includes in removing old solder

Clean excess flux off using a q-tip and isopropyl alcohol

 

thanks you for fleshing out these points. I will start out with the iron dialed down to a minimum temperature and see if thats enough to instantly melt the old solder and let it be "wicked-up" and removed. If not enough heat, I'll let the area cool down again and try again with a little more heat on the iron's tip.

I'll report back once my electronic soldering kit arrives and I've taken the plunge.


thanks again to all who've taken the time to respond.

Z

 

^^^
The proliferation of lead-free solder has caused all manner of similar issues in the race to save us from poisoning. It is more brittle than the old skool leaded stuff so joint fractures are more common.

While the solder pads & pins for the ABS power are fairly meaty, IMO a 60W iron is overkill, and a 25W would be fine, preferably temperature-controlled.

Tips for obtaining a good soldered joint:

• Use a good quality lead/tin solder as Steve suggests. The stuff used by radio & TV repairers is ideal and will contain a core of flux in the right quantity. I still have a couple of reels of 'Ersin Multicore' left from back in the day - it lasts a long time... This would be fine:
  Amazon
  Amazon
  although unless you're planning on doing a lot more like this it would be easier to blag 6" or so from your local friendly repair shop

• Ensure that everything to be soldered is clean and tarnish-free. This is key. For the ABS power, remove as much of the existing solder as possible (solder sucker is better than braid). Remove the plug from the printed circuit, clean the pin ends with some fine emery paper (fingernail emery boards work fine for this) then re-fit

• Support the board and plug so neither can move during the resoldering process

• Apply the soldering iron tip to the joint in such a way that it is heating both the solder pad and the pin, wait a couple of seconds then push the solder where all three meet. Allow the solder to flow freely around the joint. This shouldn't take more that 3 to 4 seconds max.

• Allow the joint to cool for a minute or so before tackling the other

You are looking for a shiny, smooth surface on the solder after it has cooled. A bad ('dry' or 'cold') joint has a dull, crystalline appearance.

There is an art to soldering, but it's not difficult to acquire. If you haven't done any before then I'd recommend getting hold of an old circuit board from somewhere (old radio or similar) and practising on that first.

The linked to items are certainly cheap - I paid more than that for a replacement element for my little Antex. If you do go with either of them, then be careful not to overheat the pads.

Are you planning on opening up the module or just cutting a hole in the case above the pins? I haven't been in there yet but will be doing very soon (ABS light that no longer goes away by reseating the plug). There may be some electrolytics capacitors in the module and it would be a good opportunity to replace them as PM at the same time.

 

I'm just opening a hole, so that is going to impact the way I can support the board and the pins. If this power pin re-soldering does not result in a fix, I'll pack the module off to one of the module repair outfits that I see recommended here on the forum

Z

 

Be aware that some of the repair shops will not work on an ABS module if it has been opened. At least the place where I had mine done would not.
You might want to check with your chosen shop before you try to open your module to make sure.

 

thank you for the heads up.

Since it looks like 99% of the issues with these ABS modules can be fixed with the owner doing the power pin re-soldering, I will be taking the gamble and trying it first before looking for a module repair shop that takes in "butchered" modules.

Z

 

Other than basic soldering techniques on the two failed connections, the only significant step for this job was removing the module.
I disconnected the brake lines, then bled the brake system after installation.
I did not cut a hole in the module, I separated the halves. It's not difficult, you just need to be patient and careful. A hacksaw blade is mostly what you need.
I resealed the module with black RTV and let it sit gently clamped in a bench vise overnight.
My ABS light went away and has never been seen since.

 

to me this method seems like it has some advantages over the hole saw technique. Do you think a thin Dremel Cut-Off wheel would work as good or better than a hacksaw blade ? ?

Z

 

I planned to do this the same way as stu since it 1) allows for a full inspection of the circuit board and 2) makes it a lot eaiser to re-open the case if I ever need to.

You can use a thin dremel wheel, but they get hot quickly and melt the plastic they're supposed to be cutting (I tried this method when I dismantled the centre vents). As stu says, just be gentle and patient. You only need to go about 1/8" or so deep.
I was intending to get into this today but a couple of 'honeydos' forced a rethink, so hopefully tomorrow...

If you go the RTV reseal route then it's best to use a 'neutral cure' type:- no acetic acid near the pcb.

 

I'm going to try your technique, as soon as can. Life is currently getting in the way of my car activities, so it may be a while. do you have any photos of your process ?

Z