When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
The speedometer stopped working in my 1979 F150 truck. I check both ends, going into the transmission and into the instrument cluster and they both were connected and hadn't worked themselves loose. I decided that something must be wrong with the cable and removed it from both ends. When I was taking it out, I discovered that there was a sensor midway in the cable, that I think hooked up to the cruise control in the truck.
A couple of questions.
1) Could this sensor going bad be the source of my problem? If so, is there a way to troubleshoot it?
2) Is it necessary? Can I replace the old cable with a new one that doesn't contain the sensor?
its always possible. the gear you show looks good. I would put it back in the trans and just see if the cable turns up at the cluster...that will tell you if the problem is with the speedo or somewhere in the cable/trans...
can you see the condition of the gear in the trans?
Yes that sensor in the middle it for your CC, is just an signial pick up. Obviously if the cable turns on one end and all the way on the other end, then the sensor in the middle it not the problem.
X2 check the drive piece inside the hole (on the side of the trans) where the cable came out of. And easy way to do it is to put that end of the cable back in, drive truck, does the output end of the cable spin? Also with the cable connected just to the speedo, hand spin cable on the transmission side, speedo cable bounce?
(1) Ck the sensor for input and output on the direct other side. You can take the cable off either side of the sensor and ck it that way to make sure the speedo cable shaft to sensor connection is not stripped.
(2) If it is the sensor causing the issue and your CC does not work anyway, you can take that complete cable out and get a none CC cable and put it. Just remember to put the correct/matching color gear on the new cable.
its always possible. the gear you show looks good. I would put it back in the trans and just see if the cable turns up at the cluster...that will tell you if the problem is with the speedo or somewhere in the cable/trans...
can you see the condition of the gear in the trans?
(2) If it is the sensor causing the issue and your CC does not work anyway, you can take that complete cable out and get a none CC cable and put it. Just remember to put the correct/matching color gear on the new cable.
I can't say that I've ever even used the cruise control, so if just bypassing this sensor and putting in a new cable fixes the speedometer issue, then I'm probably good with this fix.
I'd go the opposite way. Connect the cable to the speedo, & the connections at the sensor. Then spin the speedo cable end where it plugs in to the transmission, with a drill. Run the drill in reverse, or counterclockwise. See if the speedo works. If it doesn't work your way up the cable looking for the problem. Easy to do this when you don't have to drive the truck to spin the cable.
If it all checks out good, it could be a bad drive gear in the transmission.
Or the speedo head may be bad. To test, remove the cluster, stick a small screwdriver in the hole the speedo cable goes in to. Spin the screwdriver counterclockwise, see if the speedo moves. If not, time to replace the speedo head.
Rezvani's Latest Post-Apocalyptic Monster Is a Ford F-150 Raptor Underneath
Slideshow: Called the Fortress, the 850-horsepower pickup combines Raptor underpinnings with military-inspired features, survival equipment, and a starting price of $285,000.
