Using digital speedometers?
- Thread starter empera
- Start date
One other issue with the speedo cable and an aftermarket downpipe. Be very careful of the routing...if the cable is too close to the downpipe, the heat will melt the cable sheathing. All will be well...until you shut the car down and the sheathing material solidifies around the cable. Next time you move...snap! I used heat tubing on mine in the downpipe area to prevent this from happening again.
buckshotglass
I love all your sounds.
empera said:
I wish I could complain about the engine being in the way. No sympathy for you.:icon_bigg
Well mine speedo cable still works but I am still installing a Apexi rev/speed meter!! It is a fully electronic read out of speed and rpm, yet only one at a time. O well. Pretty easily installed with only 5 wires to hook up and then mounting of course. HTH
Seth
Seth
If you can't find the grease to use, there was a thread in the tech section iirc on how to get motor oil in the cable to help lube it up, I'd use a light weight oil to reduce friction inside. For those of you who have broken cables... It's an easy fix! Like 80% of the time it's the lower cable that breaks first and it's so easy to just crawl under your car, unscrew the upper cable from the lower, unscrew the lower cable from the tranny, CLEAN OUT ALL OF THE METAL SHAVINGS, and installed your SM bought lower cable (pre lubed with your choice of either grease or oil, do the upper one while you're at it) and your done! 
sethron71 said:
wheres the meter get the speed signal from?
if your speedometer cable breaks your meter wont work anymore either
Only took 28 posts before this came out... impressive, lol.lagged said:wheres the meter get the speed signal from?
if your speedometer cable breaks your meter wont work anymore either
ok folks
the electronic speedo do work. Just as always it is not direct fit.
Numerous ways to skin this cat.
1. Use the ABS teeth counter on the wheel for another mag sensor to feed the speedo.
2. Use a ford or Chevy pulse counter and adapt to R154. Feed speedo.
3. Make a 10 tooth trigger wheel and mount to driveshaft.
the electronic speedo do work. Just as always it is not direct fit.
Numerous ways to skin this cat.
1. Use the ABS teeth counter on the wheel for another mag sensor to feed the speedo.
2. Use a ford or Chevy pulse counter and adapt to R154. Feed speedo.
3. Make a 10 tooth trigger wheel and mount to driveshaft.
Anything can be done if you know how and throw enough money at it but so far nothing mentioned will supply the speed information the ECU and other systems need. Course that can be overcome too but when does it become worth it? How many new cables could you buy for all this? One new (or relubed) cable will take the car all the way to the junkyard.
Inline: The grease is called...wait for it...speedometer grease. Common stuff. I said "special" because it's really not. Any calcium or lithium based grease will work. White grease for example. If you live in a cold climate make sure it's low temp capable. Yank out the inner cable, clean off the old crap, slather it up with new and reinsert. Be sure the end gets seated into whatever it's driving. If you're anal you'll flush the sheath. If you're really anal you'll remove the cable from the car to do all this.
Inline: The grease is called...wait for it...speedometer grease. Common stuff. I said "special" because it's really not. Any calcium or lithium based grease will work. White grease for example. If you live in a cold climate make sure it's low temp capable. Yank out the inner cable, clean off the old crap, slather it up with new and reinsert. Be sure the end gets seated into whatever it's driving. If you're anal you'll flush the sheath. If you're really anal you'll remove the cable from the car to do all this.
jetjock said:
ECU does not do anything "useful" with the speed information. It won't even throw a code
The only thing that does use the speed info is the Cruise Control System which is an idependant system from the ECU anyway
The ECU does nothing useful with it? Figgie my man, you know not of what you speak. I can tell you exactly what it does and I wouldn't call it useless. No code? How about 42? Speed info is also used in more than the CC and ECU.
jetjock said:
Just for sake of argument I will say, you have the code 42,
that "speed" code 42 is the one on the dash that uses the IR LED + optical reciever to read and that is sent to cruise control with a buffered branch to the ECU. It's main function is cruise control. If it fails, the car will still run, The code will not light up a CEL but it will display during Diag.
The ECU has no speed table lookups, now the ONLY time it did was for traction control which on the 7m was not available but on the Cressida and the Soarer was.
I'm aware of how it works but you're still wrong. Speed information is more important than you think. As I said I know exactly what it does from both using my simulator and from what the factory TCCS manuals and the others I have say. Just because you can't feel anything without doesn't mean the engine is running right. It doesn't light the MIL simply because it doesn't fall under the EPA mandated conditions that require MIL activation. But I'm not going to round and round about it. We'll just have to agree to disagree. Lets just say if it wasn't important it wouldn't be monitored. Rig something to input 4 pulses/rev of the speedo drive to the ECU and it'll be happy though.
jetjock said:
4 pulses per rev?
what year is your supra?
My optical wheel in my 87's dash has about 32 spaces on it..
Come on figgie, don't confuse the TEMS steering sensor for the reed switch based magnetic (unless you have a digital dash) speed sensor. If you have a digital dash the opto-coupler is 20 ppr but then converted to 4 ppr by an internal circuit. Either way the ECU takes it in as 4 ppr. And all the other points aside I guess Toyota hooked it to the ECU and wrote code not only to use it for nothing but to monitor it simply because they were bored
jetjock said:Come on figgie, don't confuse the TEMS steering sensor for the reed switch based magnetic (unless you have a digital dash) speed sensor. If you have a digital dash the opto-coupler is 20 ppr but then converted to 4 ppr by an internal circuit. Either way the ECU takes it in as 4 ppr. And all the other points aside I guess Toyota hooked it to the ECU and wrote code not only to use it for nothing but to monitor it simply because they were bored
reed based magnetic? not in the dash and the only signal of a mag based sensor is in the r154 and Auto tranny and both are used to feed the ABS computer (not counting the two that are used to read the front right and front left wheels speed).
I can tell you with 100% certainty (that how much I tinkered with it) that the optical based signal generator in the speedo (normal analog) dash does in fact feed the cruise control, along with TEMS management with a branch off to the TCCS (as I had to take the harness out and I am the curious type).
but this is pointless, as you stated, feed the new signal and problem solved.
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Well jeez figgie, I dunno what to say. I also have an 87 and while I'm not going to go tear my combo meter out of the car I'm sitting here with my unpowered spare (which you've made me remove the speedo from) and staring at a reed switch based magnetic sensor that outputs 4 contact closes per rev while I have an ohmmeter across it, just like the TCCS books, Body Electrical Manual and 1987 TRSM says it should. There is no optical encoder in sight and the books say there shouldn't be one unless a digital dash is installed. So I give up. The point is whatever you have the ECU uses it.