Re: [MBZ] Bouncy speedo needle and wonky cruise in the 300TE
> Looks like I had a win here... Congratulations! > However to do this I would recommend a good soldering iron and a bit of > soldering experience, someone doing this as their first soldering job > with a cheap iron is asking for trouble. Worth repeating. -- Jim ___ http://www.okiebenz.com For new parts see official list sponsor: http://www.buymbparts.com/ For used parts email [EMAIL PROTECTED] To Unsubscribe or change delivery options go to: http://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
Re: [MBZ] Bouncy speedo needle and wonky cruise in the 300TE
Looks like I had a win here, finally got around to stripping the coating off and doing a bit of soldering. Big thanks to Jim and others who gave advice, it was spot on. It took two coatings of paint stripper (I found a citrus based one at my local paint place) and used a round wire brush mounted in my big drill at very slow speed. Attached the drill to a workbench and then carefully went over the board till it was all clean. I do know how to solder pretty well and managed to get it going first pass. However to do this I would recommend a good soldering iron and a bit of soldering experience, someone doing this as their first soldering job with a cheap iron is asking for trouble. Good lighting and turning the board to get best access to the solder joints is also essential, some of the solders are very close together. I also found some of the tails of the electrical bits where bent over and a bit long, pays to straighten them out and chop a bit off. Hendrik now cruising Jim Cathey wrote: >> I just want to know how the speedo and hall sensor interact, is it via >> a >> magnet or electrical connection? >> > > I don't think it's a Hall sensor, I think it's another VR sensor > that's just mounted on the rear of the speedometer (for cable-driven > ones), or a straight electrical tap for electronic speedos. Not > sure what your TE has. 126 is all electrical, 107 switched in > mid production, 201 and 123 are mechanical, not sure where 124 > sits in all that. Anything newer and you're talking to the wrong > guy. > > >> I followed the test procedures as laid out here >> http://gdl-online.com/testproc.html and all seemed fine, that is why I >> thought it might be the amplifier. >> > > It usually is, but it's nice to be sure before dropping hundreds > on a replacement amplifier! I've had a few bad stalk switches > too. Never a bad servo yet, though poor electrical or mechanical > connections have been noted. > > >> I soldered some of the connections on >> the amp but most of the amp is covered in some sort of anti corrosion >> coating which makes soldering impossible just about. >> Is there a safe way to remove that stuff without killing the circuit >> board? >> > > Paint stripper. And it's crucial that you do so if you actually > want the thing to work right afterwards. I use a methylene-chloride > free stripper. You also need to be able to solder _well_, all it > takes is one bad connection or solder bridge to keep it from working. > I use a fine wire brush (Dremel) to buff the stripped board, removing > a great deal of oxidation before beginning soldering. It helps. > Even so it often takes more than one pass over the board to get > it working again. > > -- Jim > > ___ http://www.okiebenz.com For new parts see official list sponsor: http://www.buymbparts.com/ For used parts email [EMAIL PROTECTED] To Unsubscribe or change delivery options go to: http://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
Re: [MBZ] Bouncy speedo needle and wonky cruise in the 300TE
> I did undo the speedo cable to test the hall sensor resistance It's not a Hall-effect sensor. Those are more expensive and less reliable than a variable-reluctance sensor in any situation where a VR sensor will work. And you can't test them with an ohmmeter. -- Jim ___ http://www.okiebenz.com For new parts see official list sponsor: http://www.buymbparts.com/ For used parts email [EMAIL PROTECTED] To Unsubscribe or change delivery options go to: http://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
Re: [MBZ] Bouncy speedo needle and wonky cruise in the 300TE
Yeah but the thing that has me stumped is that it only did it that one time. Usually if a MB speedo develops bouncing needle syndrome it is a fairly regular event, usually infrequent at the start and gets worse until it is a permanent feature of the car. Perhaps there is a wonky earth, the hall sensor gets power from no 5 fuse and earthes at the W1 ground behind the cluster. I did undo the speedo cable to test the hall sensor resistance and then put it all back together but then I drove 20K's to a wrecker and it was fine, it was on the way back that the needle started to fluctuate and hasn't done so since. If the speedo cable is borderline, perhaps the hall sensor firing up affected it enough to make it bounce. Apparently the hall sensor works on magnetic pulses, so as the speedo turns the magnet affected it and made it bounce. Hendrik with loads of theories and none are yet proven fact Peter Frederick wrote: > Bad hall effect pickup, maybe. The bouncing needle, actually, is > probably a bad bushing -- I'm going to have to send my speedo off for > repair, the more accurate one squeals and bounces, the odo doesn't > work in the other one. > > Peter > > > ___ > > > ___ http://www.okiebenz.com For new parts see official list sponsor: http://www.buymbparts.com/ For used parts email [EMAIL PROTECTED] To Unsubscribe or change delivery options go to: http://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
Re: [MBZ] Bouncy speedo needle and wonky cruise in the 300TE
Bad hall effect pickup, maybe. The bouncing needle, actually, is probably a bad bushing -- I'm going to have to send my speedo off for repair, the more accurate one squeals and bounces, the odo doesn't work in the other one. Peter ___ http://www.okiebenz.com For new parts see official list sponsor: http://www.buymbparts.com/ For used parts email [EMAIL PROTECTED] To Unsubscribe or change delivery options go to: http://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
Re: [MBZ] Bouncy speedo needle and wonky cruise in the 300TE
> http://gdl-online.com/testproc.html and all seemed fine See also: http://userweb.windwireless.net/~jimc/JSLcruise.html http://userweb.windwireless.net/~jimc/cwcruise.html http://userweb.windwireless.net/~jimc/SL2log.html#cruise http://userweb.windwireless.net/~jimc/mamerepairs.html Plenty of cruise info scattered in there. -- Jim ___ http://www.okiebenz.com For new parts see official list sponsor: http://www.buymbparts.com/ For used parts email [EMAIL PROTECTED] To Unsubscribe or change delivery options go to: http://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
Re: [MBZ] Bouncy speedo needle and wonky cruise in the 300TE
> I just want to know how the speedo and hall sensor interact, is it via > a > magnet or electrical connection? I don't think it's a Hall sensor, I think it's another VR sensor that's just mounted on the rear of the speedometer (for cable-driven ones), or a straight electrical tap for electronic speedos. Not sure what your TE has. 126 is all electrical, 107 switched in mid production, 201 and 123 are mechanical, not sure where 124 sits in all that. Anything newer and you're talking to the wrong guy. > I followed the test procedures as laid out here > http://gdl-online.com/testproc.html and all seemed fine, that is why I > thought it might be the amplifier. It usually is, but it's nice to be sure before dropping hundreds on a replacement amplifier! I've had a few bad stalk switches too. Never a bad servo yet, though poor electrical or mechanical connections have been noted. > I soldered some of the connections on > the amp but most of the amp is covered in some sort of anti corrosion > coating which makes soldering impossible just about. > Is there a safe way to remove that stuff without killing the circuit > board? Paint stripper. And it's crucial that you do so if you actually want the thing to work right afterwards. I use a methylene-chloride free stripper. You also need to be able to solder _well_, all it takes is one bad connection or solder bridge to keep it from working. I use a fine wire brush (Dremel) to buff the stripped board, removing a great deal of oxidation before beginning soldering. It helps. Even so it often takes more than one pass over the board to get it working again. -- Jim ___ http://www.okiebenz.com For new parts see official list sponsor: http://www.buymbparts.com/ For used parts email [EMAIL PROTECTED] To Unsubscribe or change delivery options go to: http://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
Re: [MBZ] Bouncy speedo needle and wonky cruise in the 300TE
Just a bit too much coincidence for my liking, this is the first and only time that the needle bounced in that car and the first and only time that the cruise even remotely worked. I just want to know how the speedo and hall sensor interact, is it via a magnet or electrical connection? I found a picture of the sensor on Rusty's flog a part website and it doesn't really show much but it would appear the the sensor is not the most expensive part of the set up. Might try and see if I can get one out of a wreck for a few dollars and see what I can see. Might go to a self service wrecker and pull a instrument cluster apart to see how it all works. I followed the test procedures as laid out here http://gdl-online.com/testproc.html and all seemed fine, that is why I thought it might be the amplifier. I soldered some of the connections on the amp but most of the amp is covered in some sort of anti corrosion coating which makes soldering impossible just about. Is there a safe way to remove that stuff without killing the circuit board? Anyway that ABS light is coming on again, which takes precedence over luxury items. Hendrik who likes the smoothness of the 124 but hates the electrics Jim Cathey wrote: >> how does the speed sensor interact with the >> speedo and why would it cause needle bounce. >> > > I don't think the effect is causal. Coincidence? > > -- Jim > > ___ http://www.okiebenz.com For new parts see official list sponsor: http://www.buymbparts.com/ For used parts email [EMAIL PROTECTED] To Unsubscribe or change delivery options go to: http://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
Re: [MBZ] Bouncy speedo needle and wonky cruise in the 300TE
> how does the speed sensor interact with the > speedo and why would it cause needle bounce. I don't think the effect is causal. Coincidence? -- Jim ___ http://www.okiebenz.com For new parts see official list sponsor: http://www.buymbparts.com/ For used parts email [EMAIL PROTECTED] To Unsubscribe or change delivery options go to: http://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
[MBZ] Bouncy speedo needle and wonky cruise in the 300TE
Here is something odd, yesterday after visiting a wreckers to try and find a cruise amplifier the needle on the speedo started bouncing around, just so happened I switched the cruise on and low and behold there was action. Not very good action but life nonetheless. I know that the cruise gets it's road speed from the sensor on the back of the instrument panel but how does the speed sensor interact with the speedo and why would it cause needle bounce. This morning the needle was steady as a rock and no cruise, very strange. Hendrik and his haunted TE ___ http://www.okiebenz.com For new parts see official list sponsor: http://www.buymbparts.com/ For used parts email [EMAIL PROTECTED] To Unsubscribe or change delivery options go to: http://okiebenz.com/mailman/listinfo/mercedes_okiebenz.com
