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electronic speedo

Posted: Mon Feb 11, 2008 7:06 pm
by krick3tt
Noticed an issue today as I glanced at the 'new' VDO electronic speedo. It was flashing test and dropping back to '0' MPH over and over. Could not get it from the distance to the trip setting for about three min. I may have to reinstall the original, glad I saved the parts.

Any ideas on this fantastic electronic wonder?

Morris

Posted: Mon Feb 11, 2008 9:37 pm
by pcolette
Mines been working fine so far but only have about 100 miles on it.

I'd check to make sure the sensor hasn't loosened up. I had a tough time getting mine secured to my liking. Finally added a little Loctite.

Paul

electronic speedo

Posted: Mon Feb 11, 2008 9:44 pm
by krick3tt
Thanks Paul, I'll check it in the am when it's light and see what gives.

Posted: Mon Feb 11, 2008 10:07 pm
by David Dunn
Morris
Ive had problems with only with the speedo I added to my Haf, I believe it may be a ground problem. just haven't had the time to look at it.....never had any trouble with any of the 3 done in Pinzes

Check all your connections

DD

Posted: Tue Feb 12, 2008 4:18 am
by Anthony
These electronic VDO speedos can some one tell me a little more about them. Most of the ones that I have seen are calibrated to ridiculous speeds like 160mph and more, on a small clock face this does not allow much visual accuracy. How easy is it to set them up? Are the sensor probes vulnerable during off roading and wading? Where are the best places for sensors?

Posted: Tue Feb 12, 2008 8:58 am
by David Dunn
Anthony
The speedo heads are made in varies sizes, and diffferent speedo ranges to fit where the original one was.If my memory serves me right, the 710/12s use a 3 5/8" dia., 716/18s use 3 3/8" and Haffys a 4" dia. The halls sensor fits into the original sender's fitting mount (all pinzes and Hafs are the same) . Calibration is easy and reprogramable for tire size changes.

Dave Dunn

Posted: Tue Feb 12, 2008 9:10 am
by Anthony
Dave, the sender fitting you say fits in the original mount do you mean it screw into the gear box were the cable goes in or screws into the end of the speedo cable at the head end? Mine is a TGB but I imagine its all very similar. :? I am sorry if the question appears a little dumb but I have simply no idea. :?:

Posted: Tue Feb 12, 2008 10:26 am
by Jim LaGuardia
Yes, it replaces the cable and attaches to the speedo gear housing on the diff.

Posted: Tue Feb 12, 2008 10:43 am
by David Dunn
Anthony
The Pinz pick sensor is in a different place than most vehicle. If you pull your cable at the gearbox, it probably will be the same metric thread as the Pinz. As far as the speedo head, you can measure the hole and get the same diameter....buttttttttttttttt if on the Volvo, if it is a multi function head (ex.. oil/charge lamps, turn indicators) you'll need to add provision for them elsewhere.

Dave Dunn

Posted: Tue Feb 12, 2008 11:07 am
by Anthony
Thank you Dave, I am not sure what I shall be doing just yet. What I would like to do is leave the present clock in place but have a stand alone mph clock as well. I managed to get away with making a card mph disc around the outside of the km clock, a bit amateurish but works at least in daylight. :lol:

Posted: Tue Feb 12, 2008 11:40 am
by David Dunn
Though not accurate, I just multiply the kph by .6. Easy to do in my head...60kph = 36 mph, 90 kph = 54 mph....

The real factor is a bit higher, but for a quick estimate in your head, and for as accurate as some of these old speedo are, close enough
100kph is closer to 62mph...but the .6 is good enough for some one that learned their multiplication tables in school :roll:

Dave Dunn

Posted: Tue Feb 12, 2008 7:24 pm
by andy
Anthony, have you ever considered getting a GPS unit? One of the ones I have mounts nicely to the windshield right above the windshield wiper motor and tells me exactly how fast or slow I'm going. I normally don't worry about ever getting a speeding ticket on the highway since the speed limit here is either 75 or 70 mph. In town is a different story.

Regards,
Andy

Re: electronic speedo

Posted: Tue Feb 12, 2008 11:26 pm
by w5yk
krick3tt wrote:It was flashing test and dropping back to '0' MPH over and over.
Morris
Those speedos do a self-test when volts are first applied. The display says "test" and the needle sweeps to full scale and back again. Then it displays the miles. I suspect you must have a dodgy connection to ground or to 24V. It would be worth taking it out and seeing if it behaves itself when solidly connected to 24V.

Posted: Wed Feb 13, 2008 4:31 am
by Anthony
That is a good idea using a GPS Andy. I presume that they are very nearly 100% accurate and most probably the bottom end ones are cheaper than electronic speedometers.

Just one question how fast do they respond to changes in speed?

The scenario here, even in the country, are changes in speed limits, on the normal single carriageway roads from 60mph to 50mph. When approaching a village it can go down to 40mph then 30mph and sometimes in built up places like near to schools 20mph Some of the longer villages change from 40 to 30 and back to 40 constantly as your driving through. It is the speed detection vans, fitted with long range cameras, that are the big problem here. One never knows where they will turn up next, once you have seen it it will be too late. They are very sneaky, they will try to catch poeple on down hill sections or just over the brow of a hill, where one might have had to use a little extra throttal to climb, when one crests if the accelerator is nor pulled back in time their will be a momentary gain in speed and this is what they wait for. We are told here that it saves lives and is for safety but it is all for revenue. :twisted: I have never seen a camera outside of any school or near any real danger spots, just places were folk will most likely be caught. :twisted: Wales has the highest density of speed detection cameras in Europe! :roll:


Andy wrote:Anthony, have you ever considered getting a GPS unit? One of the ones I have mounts nicely to the windshield right above the windshield wiper motor and tells me exactly how fast or slow I'm going. I normally don't worry about ever getting a speeding ticket on the highway since the speed limit here is either 75 or 70 mph. In town is a different story.

Regards,
Andy

Posted: Wed Feb 13, 2008 7:37 am
by andy
Anthony, I trust 8 satellites more than a 30 year old cable. No adjusting for tire size etc. More normal routes for the Pinz and in town are pretty predictable and I know most of the speed limits so that is not a major problem for me.

All of that being said the GPS changes pretty much instantly and my Delorme unit even goes so far as to show tenths of a mile per hr. I haven't used it but I'm pretty sure it will read in kilometers too. I look at mine usually in town and I watch it to see deceleration and how much is actually bleeding off going up hills.

Are the vans radar vans or camera? There is a "paint" on the market here that will pretty much defeat camers You can also buy things that will block/scramble radar and lasers bu they work at a distance. In the scenario you describe they might not work. The way to fight back on speedtraps is to get as many people as possible to post locations on the internet. There is a website here in the US that lists the places that are known as speed traps. Crummy little places where the speed goes from 70 to 55 and then in less than 100 meters it's a 45 or so. I quit speeding when I retired and no longer could carry my badge. :wink: That and the older I get the less of a hurry I'm in.

Regards,

Andy