Dave Carney

Just removed my old RCDLR board which is failing at temps below 45 degrees as discussed on Yeller Z06's "silly door unlocking" thread in this forum. I was hoping t see some screaming obvious soldering defect but at first glance here I'm not. You folks in the know, please let me know if you see something. Dano523 said to give a hard look at the big pins toward the back that attach to the wiring harness. Thanks.




et me know if you spot something.

GMJim

I use a large magnifying glass to look at those solder joints. If it's a temperature sensitive connection it's likely a micro crack not visible to the naked eye and sometimes it's best to re-solder them.

Dave Carney

Bottom row of pins, 3rd pin from the right. Do you see what I see?

87SAM

Hard to tell from the pictures. As GMJim said inspect with some sort of magnifier.

Dave Carney

Female side of the same connector. Here it is the 3rd from the left, bottom row.

87SAM

I sure do!

Dave Carney

I hit it with some Deoxit D5 and a toothbrush, both sides. Then a drop of Deoxit D100 in the female side. Put it back together. Now I'll let it chill tonight and see what happens when it's cold. Hard to imagine I could get that lucky.

Dave Carney

Yes, I used my big lighted work desk mounted magnifier. I didn't see anything with that but I'm not an expert. Found the pin corrosion just tilting it this way and that to change the light angle.

GMJim

That pin has some corrosion on it. Good find.

Dave Carney

If I'm reading this connector diagram correctly, they are showing the female side of this connector. So, bottom row third from the left is "P" which is the Trunk Release Switch Signal. The exterior door handle switch signals, left and right are on either side of the pin that had corrosion. So, I'm maybe 30% less hopeful now but we'll see what happens tomorrow.

yeller z06

So, I was thinking about this issue this past weekend. We (we being me and Dave and perhaps others as time goes on) have issues where the car will occasionally not unlatch the door. And the RCDLR boards are (or are becoming) NLA, and there probably isn't enough demand for someone to manufacture a replacement. So I thought, what about a kludge? Get some kid (or grown-up) who understands how to design and build logic boards, and create one that will accept the plugs that go into the RCDLR board and has outputs for the female equivalent, as a pass-through. Because if I had to, I could get by with a slightly reduced functionality if it replaced, you know, no functions.

Follow me so far? Now this would not allow the door locking system to work either, but I'll bet that most of us garage our cars. This is America, right? LOL, just kidding, j/k to our British and European friends here.

So, this module receives the signal from the door button, and it triggers the signal to the corresponding latch to, you know, unlatch. Now, if this is all 12V, then it's really simple. If it's microvolts, it's a little more complicated, detecting and sending the correct voltage, but it can be done. No worries about a fob, not checking to see if the car is locked or not. Now, the hard part is the window indexing, I don't know how that works... I presume a signal is sent to the door's window motor, but only if it's up all the way. That may be an entirely different logic circuit in the BCM.

I'm just trying to come up with an scenario simpler than unlocking the hatch with the key and using the emergency release cable.

I drove the car last night, it was 35 degrees (car sat outside all day in about 40 degrees) and the car was unlocked. The first push of the door switch did nothing, no light, no window. The second push opened the door. Perhaps it had taken a nap? I last drove the car Sunday (the day before).

C6ToGo

Not likely to help in your case, but I have gone online in the past to get illustrations of what to look for.

Dave Carney

Yes, that's the same pic I use for reference since I don't do this kind of thing a lot.

Dave Carney

In way of update when I got up this morning the car was at 41 degrees. Typically, it would fail at this temperature, but it worked fine after cleaning off the corrosion and treating with Deoxit. However, I want deeper cold than this for testing because I'm too close to the 45 degree temp that was kind of the cutoff/fail point. So I opened all the doors in the garage to let the temp drop some more. It won't get higher than 37 today so we'll see what happens. I'll post up if something changes.

C6ToGo

Since replacement RCDLRs are one of the C6 parts that has become scarce, it is one of the parts I added to my "in case I ever need it" inventory.

Got a used low mileage pull on eBay from a salvage car parts dealer. 35 bucks.

Dave Carney

I found and bought a brand new one last week after an extensive online search. They'll have to pry it from my cold dead hands because that's how long I'm keeping the car. It will go into inventory if I don't need it this week.

Corvette_Ed

I started having this same issue last year. Luckily I live in AZ where it doesn't get below 40 very often, but it's not fun trying to open the car up when it's that cold out and pitch black outside. Waiting to hear your results.

1Hotrodz

Could it be it's not the RCDLR and just a dirty touch pad on the door handle? My '08 would not open the door on the first or second try. Cleaned the pads on the touch pad and haven't had a problem since.

Dave Carney

RCDLR is down to 36.0 F right now and still functioning properly.

Dave Carney

No, it can't be. I'll save you the trouble of reading the other thread, it's pretty long.

In fact, before I get more replies with "change the fob battery, check the car battery", etc, here is what I have eliminated with as much certainty as you can possibly have with an intermittent electrical problem:

For my car it is not:
1) Dirty door pad switches
2) Bad fob batteries
3) Bad fobs
4) Bad car battery
5) Door actuators