Remote access failure on 2002 SR5 AC

New guy here, long time second owner of 2002 SR5 Tundra AC, 122K on the clock, west coast rig all its life. Great truck, highly reliable, we take it anywhere. Recently my lone original remote access key fob stopped working. This led to the events listed below. I've read many threads on related topics in this forum and elsewhere but have not found one that covers this exact situation.

- Initially we assumed the battery in the fob was dead. Our truck was factory built with the RS3000 alarm system, it has an LED indicator just to the right of the dimmer knob on a small panel to the left of the steering column. For years we’ve observed this light flashing intermittently when the truck is sitting in our driveway. Never gave it much thought.

- Got a new battery for the fob, remote access lock/unlock function resumed working for several days, then quit. We assumed the new battery was bad.

- We had always intended to get new fobs and since the original was looking worn, ordered 2 new aftermarket fobs with correct BAB237131-022 number to match the original fob.

- Received new fobs, removed kick panel under steering column, located RS3000 ECU to the right of steering column more or less above gas pedal.

- With key ON, depressed green button on ECU for 3 seconds then pressed top button on new fobs. Each time heard a double click from the area of the ECU. Tested fobs for remote access function (lock/unlock), neither worked.

- As a test, installed fresh battery in the original fob, now the remote access function did not work with it either.

- At this point, none of the 3 fobs would lock/unlock the truck. The alarm system appeared to be non-functional, the red LED did not come on at any time. Suspecting the RS3000 ECU module, we looked for some way to get a response.

- Reading a manual for the RS3000 VIP system from a 2001 Tacoma we found the section on Programming and Adjustments. Wondering if the Tundra could somehow be in Valet mode (remote access should still have worked) we decided to experiment. Using the original fob with key ON, we held both fob buttons down for 2 seconds and released. As advertised, the red LED came on, we pressed the top button on the fob and the system went into Passive (Automatic) Arming ON mode. Turning the key to Lock, the system chirped 3 times and the exterior lights flashed 3 times. Closing the door resulted in the red LED flashing intermittently. Opening the door for more than 15 seconds caused the horn to honk and the exterior lights to flash.

- This would seem to indicate the original fob is still linked to the RS3000 ECU, however it will not lock/unlock the doors.

- We repeated the procedure for Operational Mode programming and set the system to Passive (Automatic) Arming mode OFF. Worked perfectly but the fob is still unable to lock/unlock the doors.

- Tried the procedure for Operational Mode programming with the 2 new fobs. Works with one but not the other. The one that works is unable to lock/unlock the doors just like the original.

- Now we have 3 fobs, 2 of which seem to be paired with the RS3000 ECU but none of which will lock/unlock the doors.

- We’re considering erasing all remote control codes from the system and starting over but it would be a shot in the dark as we have no reason to believe this would make any difference.

- The RS3000 ECU module appears to be working but for some reason the lock/unlock signal is not activating the locks. The locks work normally with the toggle switches on the arm rests as well as with the key from either door so we know its not a problem with the lock motors.

We've checked all the fuses and read all the information we can find, has anyone experienced this particular problem? Help would be greatly appreciated.

 

This would be my next step. I have RS3200 so I can't speak to your exact point, and I haven't seen a similar issue (my memory only goes back a few years) but I'd wipe all fobs to take them out of memory, confirm they're not paired, then re-pair one at a time.

 

And if that fails, then consider that the system might just be failing overall. It’s old and these tend to have a lifespan of about this many years for a lot of the people who come to this forum for advice. It’s not a factory installed option, but a port or dealer installed system. Could be time to replace.

 

Thanks Shifty and Knabores. Tried clearing the RS3000 ECU of all fobs, turns out that function is not working. So we're back to suspecting it as the problem. I'm going to pull it out of the truck, open it up and inspect the printed circuit assembly. Meanwhile we found another one online so have that coming as well. I guess we could remove the ECU from the truck entirely and plug the harness into the base of the lock cylinder assembly. Everything should work but we wouldn't have remote access which my wife wants and so do I.

 

Update on remote access problem. Pulled the RS3000 ECU out of the truck, it was a PIA given the location and my fat fingers. But it did come out, peeled back the insulation and opened the case looking for corrosion or signs of anything awry per recommendation of speedtre in this thread: https://www.tundras.com/threads/2002-tundra-rs-3000-remote-alarm-system.42511/ The printed circuit board was pristine, looked like it just came out of a cleanroom. My wife found another ECU online at a reasonable cost, we placed the order and waited. A week later it showed up, an exact match for ours. Installed the unit and attempted to clear all fobs with these steps:

To erase all remote control codes from the system:

1: Insert key into the ignition switch, and turn it to on.

2: Press and hold the ECU programming switch for 3 seconds. The status monitors LED turns on for 5 seconds.
***You must perform the next step within 5 seconds***3: Press and hold the ECUs programming switch for over 2 seconds again. The status monitors LED turns off, then flashes 3 times. The piezo chirper chirps 3 times and the exterior lights flash 3 times.

4: Turn off the ignition. The ECU has cleared all remote control codes. Until another remote control is programmed, the system will not work with any remote control.

At first it worked no better than before. We read another thread citing how critical the timing and number of seconds are in getting the module to respond correctly. So I asked my wife to come out and watch the red LED on the dash since I can't see it from underneath. We found it came on faster than expected, more like 2 seconds instead of 3 and it didn't stay on as long as it should. So we started using the light as our trigger and voilà, the damn thing worked! Next we tried pairing our original fob and found that once again it had drained the battery in a week's time. So we abandoned it and tried one of the new aftermarket fobs. Initially that also failed until we used the bottom button instead of the top for pairing. It's not supposed to matter which one is used but on these fobs it does. Using the bottom button we got the correct response from the RS3000. Closed the doors, hit the bottom button. A heavenly chorus sounded from above, the clouds parted and the sun shone. The doors locked. Hit it again and they unlocked. Cycled them several more times, worked perfectly. Grabbed the other new fob, paired it with the same process and same result. Now we have 2 working fobs with keys and the alarm system is working as before. My wife is ecstatic. She even has the unit set to lock and unlock the doors when the key is turned on and off. Not something I care about but she does.

In retrospect, I'm not sure there was ever actually anything wrong with the original RS3000 ECU. My guess is it was using the programming button with verbal counting instead of the LED indicator. In practice, counting didn't work the way it should have, the intervals are different than advertised. But we are not about to swap it back in to find out.

 

Glad you figured this out!

thanks for the detailed posts as I am sure they will help others with the same issue.

It appears you joined the forum to ask about this specific issue. I hope you stick around, we could use some more detail oriented folks like you. Also, your writing style is a pleasure to read!

 

I definitely warn people about the timing with RS3200, but typically more about the cadence versus the count. You really need to keep a consistent rhythm with RS3200 (I've never programmed RS3000).

This is also the 2nd (or maybe 3rd) time I've heard someone had only one button work for programming versus both.

Glad to see you got it working, and even happier you posted back with an update. You'd be shocked at how many people don't bother. Sometimes makes members here wonder why they bother replying when it happens a few times a week.

I gotta ask: What plans are next on the truck?!

 

Thanks guys for the kind words. Regarding the Tundra, it needs a few things. One of the oxygen sensors is not working, at least according to the indicator light and my scanner. More annoying is another light saying the passenger side airbag is disabled, my scanner says there is a short. I can fix the oxygen sensor but am more leery of the airbag problem. Maybe I will find some useful tips on this forum as I already have for other stuff.

And then there's the original timing belt that's never been changed. I've done one of these on a 4.7L, it's a long weekend PIA. I haven't worried about it too much with this truck because we live in such a benign environment. But nothing lasts forever so its on the slate for this fall. After that, who knows? We have too many trucks as it is (we have a farm) but the Tundra is such a handy run around town rig I would not like to see it go. It's in great condition for a 23 year old vehicle. Did I say around town? It can just as easily run up and down I-5 at 75 MPH all day long if you want it too. Anywhere from Grants Pass, OR to Olympia, WA and all points between. So we'll see.

 

If your scanner reads actual SRS codes, what was the code....B???.

There are pretty decent SRS troubleshooting steps contained in the Factory Service Manual(FSM). It helped me troubleshoot a RH pretensioner short problem....B0130

 

We're seeing 2 codes, B1100 and B0108. Haven't spent much time on this, from the little I've read the SRS system has an ECU similar to the RS3000. Guessing I'll need to find it, would you know where its located on a 2002?

 

FSM can be found in Mega thread for troubleshooting.....Copy of tundra_fsm-2000-03.pdf - Google Drive

All 1st Gen Center Airbag Sensor Ass are locating on the floor and the connectors are yellow.

 

Kickass info (as usual), also think it's wise to add a friendly warning for @ProjectFool on this one, in case he's not aware.

ALWAYS disconnect the negative battery cable BEFORE you disconnect or reconnect any yellow connector in any vehicle, ever. Do not reconnect the battery until all connectors are re-secured.

Disconnecting or reconnecting an airbag connection with a live battery can result in you eating an airbag, serious injury. In some vehicles, disconnecting an SRS/yellow connector with the car powered up can set codes you cannot delete without a specific type of diagnostic tool that allows clearing SRS codes.

 

This is great stuff guys, what a jump start! Thanks for posting. I found the FSM and downloaded it. Looks like if I remove the lower center cover I can access the SRS ECU. I'll be sure to disconnect the battery before pulling any plugs, testing. It will be a few days before I can get to it, when I do I'll post an update.