I am a newbie to this forum and have a 2000 TL with an electrical problem. Symptoms are: lights-on and key-in reminders go crazy when key is left in ignition when drivers door is open; dome light don't work when open driver's door; security system will not activate with the remote; intermittent wiper and driver side rear power window malfunction; intermittent dash light brightness control malfunction; headlight auto-off function does not work. All problems started at the same time. After reviewing schematic, I think the problem is a faulty Driver's Multiplex Control Unit. Anybody know how to diagnose for sure, and is it hard to replace myself? Nearest dealer is 3 hrs away. Thanks for any help.

 

Nobody out there with similar experience? Would appreciate your thoughts. Thanks

 

ss2003,

I have far few issues on my 02, but suspect the same problem. Changing the control unit appears to be very simple, and the unit is not terribly expensive, about $125 if I remember. There is a diagnostic connector tool that actuates a self test, flashing codes on the dash indicating the various sensors and switches. My problems are the security system doesn't work, the lights don't auto shut off and, if left on, the engine doesn't shut off with the key removed! In my case, none are significant enough for me to really dig into the problems. The local dealers are willing to look at it, for $100 an hour.
I think the controllers are the same as on a Honda Accord of the same vintage, but don't know for sure. A junkyard would know and would be more reasonable than a dealer. I don't like swapping parts without performing the self test diagnostics. Where are you located?
Miner

 

Miner,
Thanks for your reply. Sounds like the diagnostic tool is a dealer item, not the OBD II scanner? We do have a Honda dealer in town (Redding, CA) as well as Honda-only shop. I'll make some calls tomorrow. Thanks

 

ss2003,

The diagnostic tool looks to be a jumper wire that connects 2 of the 3 terminals, but it isn't clear from the service manual. When I looked into it, it appeared to be a common tool between Hondas and Acuras and the way it flashes codes reminds me of the original diagnostic functions on the first computer controlled cars.
I'd call the Honda dealer and hopefully they'd be willing to test the system. Even though something like this is common to the Accord (and Odyssey and Pilot) they may not want to make the effort. Good luck. I'm kind of in the same boat, the Acura dealers are accross the sound (about an hour or so) and it is a pain to ever go to them.
Miner

 

Miner, I ordered a new control unit from my original dealer for around $100 (can find it cheaper online) and installed it today. Fixed all my problems! Not hard to do, just a little tedious. Had to remove the connectors on both sides of the fusebox. Took about 2 hours to disassemble as some of the connectors were pretty tight, snapped in the new unit and only took about 10 minutes to reassemble and reconnect the battery. If you decide to do yours, let me know and I'll give you more details. Oh, according to Acura, it is not the same part as the Accord.

 

SS2003,

Did you decide to replace the control unit after diagnostics or just invest in the control unit as the troubleshooting? I know that Honda and Acura use different part numbers for the same parts but in this case, there could be differences in the items controlled by the units, as I don't think Accords come with memory seats or some of the Acura-esc features.
I'd like more details about replacing the module. I believe it involves removing the lower panels and I'm sure there are some tips you can give to help me out.
Miner

 

I decided to just go for it. The part was probably cheaper than diagnostics by the dealer. OEMAcuraparts.com has it for about $63 but I went with the dealer so I could ask questions. Here is what I did:
1. Disconnect battery (-) terminal 1st. Make sure you have your radio code.
2. Pull off fuse access panel.
3. Remove lower panel by driver's legs: 1 screw visible when you take off the access panel, and a bunch of clips.
4. I sketched out the fuse box and numbered each connector terminal, disconnected all the connectors one at a time on the door-side 1st and labeled each one with masking tape. They have a locking tab on each the side that has to be pressed in before you can pull the terminal off. Some of them were very snug and I had to tease it along with a small screwdriver while depressing the tab. Then I did the same on the driver side of the box. The one problem I had was a yellow connector that looked like it had double-locking tabs, and it was for the SRS system so I left it alone Would have made it easier if I had gotten this one off, but didn't want to mess up the air bags.
5. Remove the 10mm bolt holding the fusebox; it is on the door-side of the metal frame behind the fuse access panel. There is a plastic "clip" on the bottom of the fuse box and a slot on the top that a metal tab slides into. Open the clip a little and wiggle the fuse box out. This is where it would be nice if that last yellow connector was off so you could do the rest on the bench, otherwise it is just tight quarters under the dash.
6. Look at your new control unit to see where the locking tabs are and it will be obvious where you have to pop the unit out of the fusebox. Mine took a little working around the sides too with a small screwdriver, just sliding it under the edge and sliding it from one corner to the next.
7. Snap in the new unit, and put the fusebox back in position in the metal tabs, and secure the 10mm bolt.
8. Now it is just a matter of reconnecting the wire terminals in the reverse order, and replace the panels.
9. Reconnect the battery, this time (-) last. Punch in your radio code and enjoy all the functions you had lost. (We hope) It took me about 2 1/2 hrs but now I think I could do it in less than one.

The part # is 38800-S0K-A02. Supposedly controls more bells and whistles than the Accord.

Good luck and let me know if you have any questions

 

SS2003,

Thanks for the instructions. Now if I can get motivated enough to order the part and then install it. My problems like the lights staying on and the security system not working are not quite enough for me to do the job. I have on a couple of occasions had the right turn signal stay glowing even with the left turn signal flashing. Shutting off the car has usually fixed it; perhaps this is what I need.

Thanks

 

I was wondering if replacing the control unit actually works for you guys im having the same problem Dashboard lights out and security system faiulure ( driver door wont closed with the remote) i check everything and yeah it seems that the box is the problem