Speedometer Fix

Buzz Lightyear

New Member
Jul 12, 2013
8
0
0
Bay Area
My 90' supra has been sitting do to the fact that I need to replace the injectors, which I'm doing soon, but my speedometer gauge doesn't work. The RPM's, Fuel, Boost, and Oil all work except for my speedometer.

I would like to know where exactly the wires are placed for the speedometer and if its an easy fix to do myself.

Help would be much appreciated,
Thank You
 

1James

Lurker
Mar 19, 2009
60
1
8
Bay Area, CA
The speedo is driven mechanically by a cable that runs from the dash to the rear end of the transmission. For a manual car, there are two cables, as seen in the diagram below:
118919510.png


With a little bit of testing, you can determine which of the two cables is damaged (or both) and order the appropriate replacement.

Toyota Part Numbers:
Lower (short) cable: 83710-14800 ~$15
Upper (long, expensive cable:83710-14731 ~$90

My source/Purchase Link (NOT an advertisement or endorsement): http://www.toyomotorparts.com/components/toyota-1988-supra_meter-83-01-11096_3.html

Driftmotion also resells these on their website if you do not want to go through a Toyota Parts Dealer: http://store.driftmotion.com/static/i-speedocablemk3supra.php
 

supraguy@aol

Well-Known Member
Dec 30, 2005
4,236
37
48
Atlanta
Its not uncommon for either the upper or lower section to fail.
The easy test is to disconnect the input on the passenger side of the transmission, and disconnect the short cable from the long section. Check to make sure that spinning the input side of the short section results in spinning at the output side. Then, put the long cable's shaft into a cordless drill chuck. Don't over tighten it. Run the drill. In one direction or the other, it should cause the speedo to display a speed. If it doesn't move your speedo needle at all, then you've confirmed that the long cable is bad, or possibly, that the speedo itself is bad(a less common occurrence). Either way, you'll need to remove the gauge cluster. Once you do, you'll see the other end of the long cable. At this point you can determine which component is faulty.