Hardtop - 91 300SL - Trouble Codes

[bbrewer]

Small problem, I hope, but I have a 1991 300SL, and am having a trouble code occur whenever I install the hardtop on my car...

Both the softtop operation and the hardtop operation perform well, and I wouldn't think I have any top-related problems with either top if it wasn't for the blinking light. If I'm just putting the softtop up or down, the red light is on during operation, and off while I'm not working with the top, so no problems there.
But when I install the hardtop, the top switch light is on a solid red while the car is stationary, and a blinking red light while the car is moving..... The top seems to latch correctly, both front and rear, while both snugging it down and releasing it, yet the light indicates otherwise.

I have checked and cleared (I "think" I cleared them, they keep coming right back) the two codes, but I keep getting code #18 and code #20.
My understanding is that code #20 means the hardtop is in place with no faults, but the light also keeps indicating otherwise...

Any advice or leads on what to look at first would be much appreciated.

Thank you very much.

[waybomb]

I think you have to clear codes twice, until you get the single flash, if I recall. Do a search for my user name in this forum - I had a problem when my battery died and the guys here really helped out. In one of the posts, all the codes were listed.

[bbrewer]

Well, progress... I think....
Now all I get is code #20, which I can't seem to clear, and which "should" be "top on - no faults determined".
Which is true, and is a good thing, except that the red switch light stays on whenever I'm driving the car... :-(
If the car is idling but stationary, I get a solid red light.
If the car is moving, it just blinks until I bring the car to a complete stop again. Then back to solid... :-(
Works great, you just wouldn't know it by the switch.

Any thoughts at all??

Thanks.....

[waybomb]

I'm a greenhorn on this, really. All I know is what I learned when my battery went dead and ecerything seemed to go haywire (don't ever let your battery go dead!)

Just a thought, did you pull the codes with the car running or off? Maybe with it running it will give you the code that's causing the flash? Maybe there's something with a wheel sensor giving the soft top controller mis-information?

Is your ABS light on? Maybe, like on mine, one of the red ATO fuses on top of the OVP blew. The OVP is under the cover in the engine compartment below the windshiled in front of the passenger. Mine was orange, had a clear cover, and had two ATO fuses. They both looked ok, but when tested with a voltmeter, one was blown, causing all sorts of grief.

[bbrewer]

Just an update...
With the hardtop on, I can only get a Code #20 to flash, which should be "No faults, top on the car".
So I took the top off the car, and I can only get a Code #1 to flash, which should be "No faults, top off of the car".

Sounds great and both tops function just as they should, but when the top is on the car I still have the red switch light on solid....
Interestingly enough, when I pull the hardtop OFF of the car, the light goes off, as it should be all of the time when not actually using the switch....

Bobterry, where are you when I need you??

Thanks....

[bbrewer]

Well, problem solved...... kinda.....
Turns out the front left header latch wasn't snugging the hardtop down quite as well as it could (or should)...
I used the 6mm allen wrench to tighten the latch, and presto, the light went out....
I cycled the top release and snug-down cycle a few times, and everything works as it should, it's just that the left header latch requires me to firmly pull down on that corner to allow the left latch to snug it down completely....

I can live with an "almost" fully automatic closing operation... :-)

Thanks, and hopefully this string will help somebody in the future....