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My speedometer had been twitching at low speeds and I figured at some point it would need to be changed. That point arrived Sunday as when I made a trip to the store I noticed the speedometer was not functioning at all. So, I have that project added onto to others. This morning on the way to work, I tried to use the cruise cotnrol. Indicator light comes on but c/c will not engage.
Question is, are the two tied together in some manner that if speedometer isnt working, the cruise wouldnt work?
Speedo is just a cable from the tranny to the gauges...un-related to the cruise. Cruise works via vacuum, check the hoses for holes and split ends.
Thanks. Just thought it was odd that both happened to start up with problems at the same time.
But where does it get the speed signal? I always assumed it came from the speedo, so if the speedo dies then you would lose the cruise control.Quote:
Originally Posted by sammm
No?
Found this on that other Miata forum a few minutes ago:Quote:
Originally Posted by trickyrix
The speed sensor is part of the speedometer head - The speedometer is mechanical, driven by a cable and contains a speed sensor which reports to the ECU. Yes, it also drives the cruise control
Can't say I've ever read about a working speedometer which has a malfunctioning speed sensor (usually when you have no speed signal, you have a bad cable) but I suppose anything's possible
The car in question was reported to be a '96. Mine is a '95. Also, not sure if this info is pertenent to the NA or if this guy pulled this out of his nether region, but it kind of makes a little sense as to my issue.
I never knew they were connected. Thought the speedo was strictly mechanical. Keep us posted.
My guess is that if you replace the speedo cable, the cruise will magically spring to life. ;)
I'm sure I will procrastinate a couple of weeks before changing it but will let you know how it goes. :)
When I first got my 01 the speedometer would go on and off, when it went off, the cruise control would kick off too.
Rob® bent the contact in the Speed Sensor's connector towards the pins in the other end, plugged it back up, and both have worked ever since.
Obviously the NB's are different from the NA's, but my point is that the systems are connected.
The green-red wire from the cruise control unit in a 1990 goes to the speed sensor in the cluster (2F, labeled "RSW"). Not sure of the color in a 94-97, but it's the same connector on the cluster (see pic - ignore the marker, that's for something else):
http://www.guapozx.com/users/dogpile/cluster.jpg
Your speedo stops working (bad cable, stripped gear in teh trans, whatever), your cruise stops working.
And it's Rob® :P (my last name starts with an R)
Technically it is: Gear in trans -> cable -> connector on cluster -> speedo gauge.Quote:
Originally Posted by sammm
The cruise control is not. There is an electronic speed sensor that reads off the back of the gauge. The system works by vacuum, but the ECU gets sent a signal from the electronic sensor. No signal, no cruise. There's a few other electronic sensors here and that that can cause the cruise not to work, but they have no effect on the speedo/odo.