Gauge Cluster Printed Circuit Board Corrosion, Interchangeability Question

[Fleetw00d]

The printed circuit board in my 93 LX wagon (auto) had problems when I bought it a few years ago such that the speedometer and odometers didn't work because of corrosion on the printed circuit board. I installed a board from a 93 LX sedan, everything now worked, but the speedometer was off. I then installed the 130 mph speedometer from the sedan and it worked correctly.

Now that replaced board has another area of corrosion that causes all the door / hatch open lights to come on dimly all the time. I cleaned the corrosion as best I could which appears to have restored the door open function (all black unless a door is open), but now the temperature gage goes straight to HOT when you turn on the key. I'm kicking myself because I checked the function of the door open lights, but not the other functions before I put the dash bezel back, radio, and console back in.

I have an extra 93 LX sedan cluster, but its board is corroded even worse at the same location.

I was only able to find a cluster from a 93 EX sedan today at the JY with light corrosion in the same area as the two clusters above (what is it with this location?).

Any one know if the EX board will work in the LX cluster (I know it wouldn't work the other way around)? The only difference I see is the "ABS" light on the EX cluster. There is a blank space at that location in the LX cluster. Will all the other circuits work?

Any one have a clean LX sedan automatic cluster circuit board? Majestics's site indicates the board is no longer available (almost $1000 list price if it was!). With all the corroded ones I have, I may see if I can solder wires between the appropriate pins to replace the corroded circuits on the board.

12/28 01:32

Looks like I answered my own question. Installed the EX circuit board, door open warnings actually check correctly (on for two seconds) when turning the key on, temperature gage stayed cold. It's very late, so I didn't go out and drive it.

I noticed with both clusters apart that the "ABS" light is in a separate smaller circuit board at the top of the cluster assembly underneath the large circuit board. The LX cluster appeared to have the same smaller board, just with an empty light socket where the "ABS" light would be. Everything on the main circuit boards looked similar.

[BreckAConner]

If you ever find yourself doing this again in the future. I don't think it matters what cluster it is except 90-91 left plug is different from 92-93, which means it wont work, "maybe" if you change the plug head. Other than that some have different options like SRS and ABS lights at the top, but you can remove the lights and plastic piece that says that. They are fun to play with, I enjoy it.

[dj_ender]

Another thing to keep in mind, not only are the 90/91 connectors different from the 92/93, the Nippon Seiki (NS) and Nippon Denso (ND) boards are not interchangeable. And IIRC, LX/DX are also different from EX/SE.

[Fleetw00d]

Thanks, I knew enough not to try to use the 90-91 board. All the clusters I have are NS. After driving it Saturday morning, as soon as you get 1/10 mile from the house, the temp gage goes to "H". Bought an infrared temperature gage to make sure it wasn't really overheating (never miss an opportunity to buy a tool!). Checked the sensor, resistance was close to the manual specs. I wound up having to pull the cluster again and replace the temperature gage; that cured the problem.

So far, the EX board appears to work in the LX cluster.

EDIT:

And for Pete's sake, remember to reconnect the odometer connector to the printed circuit board when you reassemble it! I had to take it all apart again today just to do that.

EDIT 1/1/14 12:30 AM:

Happy New Year. Spent it taking the gage cluster out again - gas gage was reading way above full (before I put 8 gallons in it). I wound up having to replace the temp/fuel gage again! I've got to set up a way to test the individual components before installing them in the cluster and the car to have to see whether they work or not. New gage points at the "F", not way above, so I believe it is working. My daughters will find out later today on their way to FL.

12:30 PM:

At the TN border, the gas gage is working properly, but the speedometer is fast by 4 mph at 70. The EX board must make adjustments for the slightly different gearing of the EX vs. LX. Looks like my quest for a corrosion free LX sedan or wagon board is back on.

[cb9love]

Thanks, I knew enough not to try to use the 90-91 board. All the clusters I have are NS. After driving it Saturday morning, as soon as you get 1/10 mile from the house, the temp gage goes to "H". Bought an infrared temperature gage to make sure it wasn't really overheating (never miss an opportunity to buy a tool!). Checked the sensor, resistance was close to the manual specs. I wound up having to pull the cluster again and replace the temperature gage; that cured the problem.

So far, the EX board appears to work in the LX cluster.

EDIT:

And for Pete's sake, remember to reconnect the odometer connector to the printed circuit board when you reassemble it! I had to take it all apart again today just to do that.

EDIT 1/1/14 12:30 AM:

Happy New Year. Spent it taking the gage cluster out again - gas gage was reading way above full (before I put 8 gallons in it). I wound up having to replace the temp/fuel gage again! I've got to set up a way to test the individual components before installing them in the cluster and the car to have to see whether they work or not. New gage points at the "F", not way above, so I believe it is working. My daughters will find out later today on their way to FL.

12:30 PM:

At the TN border, the gas gage is working properly, but the speedometer is fast by 4 mph at 70. The EX board must make adjustments for the slightly different gearing of the EX vs. LX. Looks like my quest for a corrosion free LX sedan or wagon board is back on.

From what I've seen most Honda's around 70 mph are reading 4too 5 mph fast if you use a GPS too check your speed, explains why cops dont pull me over when i blow by them at "75" when they are out gunning with radar.
but i love your write up, my board has these burned spots as well and the only matching board i found at the JY also had these burned spots, glad too see some other options.

[Fleetw00d]

My 93 EX is right on the dot at 70 vs. GPS. My 90 and 93 LX sedans are within 1 mph (been a while since I checked 'em). Later in the trip my daughters checked the odometer vs. highway mile markers in AL; less than 1 mile difference over a distance of 100 miles, so the odometer doesn't have the same error as the speedometer.