LiCelsior

iTrader: (32)

thanks for the response OLT, anyone have a picture of their resoldered antenna?

DaveMcKenz

I think picture is in this 9 page thread.

orangecar

so i found out that my remote works when I shake the key really hard. tomorrow I'm going to resolder this thing once in for all muhahahahahha.

good post OLT

Steelwheel

Thanks OLT. Cleaned mine out and soldered the transmitter. Working like a charm. Great thread.

keinplatz

It works!! Thanks!!! Actually alarm button under the wheel was in off position so I couldn't disable the alarm I could drive though... When bridged two contacts in fuse box with a wire. (Don't think it's a good idea to write in this thread which ones to avoid potential crime...) Not an easy way, so I decided to check CL. Special thanks to OLT!

danieljava

All of the sudden, my keyless entry stopped working on my ’92 SC300. After checking the battery and the antenna on the key (sender) I did the radio test (94.9) and I did hear some noise when I pressed the button.

I tried to reprogram the remote by following this direction (and I think I erased the old program, great!):

- The key is not inserted in the ignition key cylinder
- Driver's door is OPEN (other doors are CLOSED)
- Driver's door is UNLOCKED

1. Insert the key into the ignition key cylinder, then remove it.

2. Within 40 seconds: Using the door control switch (for manual operation) move the switch 5 times to LOCK/UNLOCK at approximately 1 second intervals (so in this step, hit the lock button on the driver's door, then the unlock button a second later, and repeat 5 times)

3. Close the driver's door, then open it

4. Repeat step 2, again within 40 seconds

5. Insert the key into the ignition cylinder

6. Turn the ignition switch (the key) from ON to LOCK at approximately 1 second intervals for 1 - 5 times, depending on which mode..

Add mode - 1 time
Rewrite mode - 2 times
Confirmation mode - 3 times
Erase mode - 5 times

7. Remove the key from the ignition key cylinder

The car locked and unlocked as expected. But pressing the button on the key didn’t have any effect.

I bought another receiver ECU and exchange the EPROM with mine. Still no luck. However, soon after, I noticed that neither of the ECU units respond when trying to reprogram the key as described above anymore.

I ran a different diagnostics test described in the 1993 SC300 repair manual (not quite the same as 1992 but close) which is to:

1. Open the driver’s door
2. Using door control switch (for manual operation), switch 10 times from LOCK to UNLOCK at 1 sec intervals.

An UNLOCK – LOCK operation occurs 1 time after the diagnostic mode is entered. Within 10 seconds, if I press the button on the key (while the key is touching the antenna attached to the ECU!) UNLOCK – LOCK occurs 2 times which I’m not sure what it means. But I read somewhere that it means the transmitter is bad. If the key is not touching the antenna nothing happens.

I have measured the voltages of all the wires of the terminal attached to the ECU and everything seems ok except wire 3, 4, and 5. The voltage between either one and ground should be between 10v to 14v when the key is in the ignition and/or the ignition switch is ON but my reading is around 8.90 volts. The repair manual suggests that the ignition system is faulty.

At this point I’m assuming the ignition system developed a problem during my testing (maybe the new ECU burnt something out) and my original problem was that remote key was bad even though the FM test passed. The repair manual suggests that even if the FM test passes the key might still be faulty.

Does anyone have any suggestions or comments?

DaBunny

Okay, here's a stumper. The remote lock/unlock functions on BOTH of my keys are not working. Bought my (4-speed!) SC300 new in '93. Both keys worked until approx. 1-2 year ago, but they didn't both fail at the same time! Until recently, the one I was using most often would still work if I held it in *just* the right position about a foot from the door (too much trouble). After I bought a new battery, the response improved, but only for a very short time—a couple of weeks, it seemed.

I've read this entire thread, tried new batteries, eyeballed the solder connections (both good) and did the radio test (both failed to produce any beep or interruption of any kind). The lack of radio response would seem to indicate a failure in the key rather than in the controller box, right? But BOTH keys?? (And to the person who inquired whether anyone still has all four keys to their Lexus: You betcha!)

I have not opened the controller box (hey, I'm a girl), but I will if I have a good reason to. Any ideas?

Oh, and to the knowledgeable person who started this thread, it would be very helpful if you posted your entire set of step-by-step tests, with photos, all in one thread. At least some of us can be trusted to follow them in order. ;-)

Thanks much.

dumdumgreg

iTrader: (5)

mine's dead
I'm just gonna go aftermarket with a compustar restart start/alarm

mk4r34

iTrader: (1)

I had to bump this!!...I went through the whole procedure with the key to get to this page and realize that the remote switch was off!!!...I didn't even know there was a switch under there for the remote!!!and my battery is still good after 16 years??thanks OLT for info/patience!!!

chengxuez

mine is off, trying to fix it for the longest time

SC34M3

my range sucks hopefully this will help me
should be sticky

Gspec

Mine didnt work when I bought it.......actually took me a couple weeks to discover the button.....one trip to Radio Shack for a battery and she's working great! (Distance sucks however....and lack of lock/unlock confirmation lighting/horn honk kinda sucks....gotta hit the button while still close enough to hear the locks)

iceman400

iTrader: (5)

mine doesn't work either ... jus went outside and did the 94.9 test and appears that the transmitters are good..so tom i will perform the next step

O. L. T.

iTrader: (17)

Good stuff. Glad to see it is still helping. Over the last 6 years I've written something like 45 DIY's They pop up every now and then.

snook

iTrader: (5)

I have a 1996 SC300, it didnt come with a remote just 1 key.
So I bought the correct remote and I've tried to program it with no luck.

Do you have the correct procedure for a 96 sc300 5 speed?

Also people are saying there is a remote on/off switch under the dash that needs to be on.

I cant find that. I also had an aftermarket radio in the car but now went back to a fully working stock system but the headunit is out of another car a 97 auto does that matter?


Thank you sir for any help Ive tried everything I know to do