ABS help

[The Extractor]

My vin is posted in the thread. I cannot separate the board yet I have to desolder all the pin connections first. I think I found one on Ebay but I still want to bypass it.

 

[bwilliams60]

The only way you are going to do that is to figure out how to take your analog signal, convert it to digital and feed it into speedometer. Sounds like a lot of work. Anyways, see if you can get a picture of components side and keep this one in mind that we have here. Same as buying from EBAY. From somebody that knows, trying to bypass is going to be a labor intensive procedure. Good luck.

 

[bwilliams60]

Is that your board that you showed in the earlier post? Can you get a really clear picture of the circuit and post it here. Particularly the area where the relay sits. Larger joints.

 

[The Extractor]

Is the relay the white box?

**broken link removed**

 

[debe]

That's a beter picture & theres an obvious dry joint on the relay pin to the left or R35(bottom & about middle of picture) I would resolder all 5 pins on the relay on that board for starters.

 

[The Extractor]

The pic is deceiving because of the clear coating on it. I will remove the coating, resolder it and report back.

What does dry mean? My father was trained in electronics and I never heard that term, only a "cold" joint. It seems both are bad.

That's a beter picture & theres an obvious dry joint on the relay pin to the left or R35(bottom & about middle of picture) I would resolder all 5 pins on the relay on that board for starters.

pic

 

[debe]

Here in Aus a solder joint that has a crack around a pin like on the one mentioned is what we call a dry joint. I use a good magnifying glass or take Macro pictures of boards with suspect joints & expand the picture, to find cracks in solder joints. These are common on circuit boards that are subject to viabration or high currents in the circuit. Ive repaired lots of circuit boards from vehicle modules with intermittent faults.

 

[KeepItSimpleStupid]

Two pins left of R35 has a "suspicious" piece of possibly solder, that COULD be grounding that pin. It's between the trace and the soldermask (ground).

==

Follow that pin straight down and slightly to the left, it LOOKS like a possible component lead in the middle of the unsoldered hole. I would confirm a component on the other side first.

 

[bwilliams60]

+1 on the cold solder joint left of R35. If you have a magnifying glass (very good one), go around the board and see if you have any more that are suspicious. Also take a tiny screwdriver or similar and just nudge each of the small surface mount components. Often times they will come loose over time and create problems. Pay close attention around the relay areas

 

[KeepItSimpleStupid]

Freeze spray will also show bad solder joints.

 

[The Extractor]

Two pins left of R35 has a "suspicious" piece of possibly solder, that COULD be grounding that pin. It's between the trace and the soldermask (ground).

==

Follow that pin straight down and slightly to the left, it LOOKS like a possible component lead in the middle of the unsoldered hole. I would confirm a component on the other side first.

Im pretty certain that is not a piece of solder. It is most likely a small chunk of the clear rubbery coating all overthe circuit board which makes soldering impossible without cleaning it off first. Any suggestions on how to remove it?
I was thinking brake cleaner but that is very harsh. Maybe a short stiff bristle brush of some sort.

 

[The Extractor]

Well that didn't fix it. It's hard to solder with that coating. The abs light blinks once now and I don't remember that last time

 

[The Extractor]

Well I removed and installed the module a couple times today and the last time I installed it, it didnt trip the abs light for about 30 seconds. Weird, Im thinking bad internals.

 

[bwilliams60]

Can you communicate with the module now? You say it didn't blink once before so something has changed. Plug it in and check the voltage on the four relay points and show them on a pic of the board if you can. Use paint to show your voltages. Reference ground back at the battery negative post. Do not use any other ground.

 

[The Extractor]

I dont know what you mean by communicate with the module, you mean with a scan tool?
I installed a module I bought from Ebay, with the same result, does it need to be flashed to my truck?

 

[KeepItSimpleStupid]

Autozone will do a code scan for free. They generally won;t reset the fault, but you can provide a deposit and borrow a scan tool. Many times, you will need an ABS enabled scan tool.

 

[bwilliams60]

When I say communicate, I mean can you hook up to it with a scan tool and see data such as fault codes or any type of datastream. If you do that, we can progress further. The module does not have to be flashed to the truck. It has a read only module and is non-programmable. We ned to communicate with it and see what the codes are. If you had an analog voltmeter, I might be able to get the codes through it if I can remember how we used to do it See if you can get it scanned and get some codes that we can work from. If it won't communicate, we need to look at other things.

 

[shortbus=]

But without the ABS solenoid system, will the ABS control module even function at all? It's always my understanding that they need to communicate with each other. The module does a system check at ignition turn on doesn't it?

 

[The Extractor]

It worked fine for years without the solenoids/hyd unit plugged in.

I think I have another issue as the new unit pops the ABS light as well.

 

[KeepItSimpleStupid]

Go to an AutoZone (www.autozone.com) store and have them read the codes for free and report back. Hopefully, there is one near you.