|
|
|
Your donations help keep this valuable resource free and growing. Thank you.
|
Eagle cruise control mystery |
Post Reply 
|
| Author | |
amaurer3210 
AMC Apprentice 
Joined: May/06/2019 Location: Colorado Status: Offline Points: 119 |
 Post Options
 Thanks(0)
 Quote Reply
 Topic: Eagle cruise control mysteryPosted: May/21/2019 at 11:29pm |
|
This new-to-me 84 Eagle has cruise control... no idea if it works because the transmission doesn't work and its hard to test when you can't drive.
However... Its starting to look like something seriously stupid has taken place inside this vehicle. There were signs that someone had been behind the dashboard committing sins, and now further mysteries underneath. I noticed just in front of the transfer case there were a pair of wires running along the speedo cable that did not look original but which were hanging down, broken (they had clearly tangled with the drive shaft and lost). I just removed the transfer case and found that there is a thing in the speedometer cable, looks like a sender for the cruise control, located at the end of the cable near the skidplate. Then a short ~8" cable extension goes the rest of the way to the transfer case. It seems like there is wayyy too much speedo cable; it was routed in a huge 360 loop packed up into the skidplate.  Is this right? Or should the sender be at the OTHER end of the speedo cable, behind the dash? I'm wondering if the previous owner had to replace the speedo cable and forgot to install the sender before reinstalling the dash? So they got lazy and tried to rereoute the sender to the other end? Also is it possible that the extra speedo cable length is because they tried to install a non-cruise control cable with the extra extension cable from the sender? |
|
 |
|
|
pacerman
Supporter of TheAMCForum 
Joined: Jul/03/2007 Location: United States Status: Offline Points: 9060 |
Post Options
Thanks(0)
Quote Reply
Posted: May/22/2019 at 1:04pm |
|
The speed sender should be located between two sections of the speedo cable, not behind the dash. I advise you to get a Service Manual for whatever model year AMC you have. The 80's cars got more complicated with more emissions stuff and accessories. The decision trees in the 80's service manuals are pretty good. AMC was learning to make things easier for their service techs. There should be a wiring harness connected to that speed sensor. What looks like may have happened is that a previous owner needed to replace the speedometer cable for some reason and used a longer replacement cable for a car without the cruise control, which would have gone directly to the transfer case or transmission. Joe
|
|
|
Happiness is making something out of nothing.
|
|
|
|
|
amaurer3210
AMC Apprentice
Joined: May/06/2019 Location: Colorado Status: Offline Points: 119 |
Post Options
Thanks(0)
Quote Reply
Posted: May/22/2019 at 1:19pm |
|
I was going off of this, which I think shows the "short" cable behind the speedo...
Where exactly is the right location for the sender? Under the car or in the engine bay or inside the cabin?  |
|
|
|
|
pacerman
Supporter of TheAMCForum
Joined: Jul/03/2007 Location: United States Status: Offline Points: 9060 |
Post Options
Thanks(0)
Quote Reply
Posted: May/22/2019 at 2:02pm |
|
No 13 is the speed sensor. The don't think the drawing is to scale so the upper speedometer cable should actually be much longer than shown. I could be wrong though. At any rate, the speed sensor is not under the dash. Joe
|
|
|
Happiness is making something out of nothing.
|
|
|
|
|
FSJunkie
AMC Addicted 
Joined: Jan/09/2011 Location: Flagstaff, AZ Status: Offline Points: 4742 |
Post Options
Thanks(0)
Quote Reply
Posted: May/23/2019 at 3:29am |
|
Oh no. Seeing this is giving me brain cancer. Why do people do stupid crap?
That is the cruise control speed sensor. It needs to not be under the car, and not be connected using crimp-on butt splices. That is truly horrifying to see. It should be located in the speedometer cable about one foot away from where the speedometer cable enters the firewall grommet. This places the sensor roughly behind the brake booster where it is safe from dirt and water. The connector for it hangs off the cruise control wiring harness in that area. Relocate it back to where it belongs and get some proper electrical connections on it. Soldered, heat-shrunk, waterproof connections. The ECU for the cruise control is a yellow box under the dash, driver's side. There are some adjustment screws on that box. Do not turn them or you'll be in a world of pain trying to get them back in adjustment. I turned them in a moment of stupidity and spent two hours driving back and forth on the same section of road with the box pulled out from under the dash, turning the screws as I drove until I got the adjustments right again. |
|
|
1955 Packard
1966 Marlin 1972 Wagoneer 1973 Ambassador 1977 Hornet 1982 Concord D/L 1984 Eagle Limited |
|
|
|
|
billd
Moderator Group 
Forum Administrator Joined: Jun/27/2007 Location: Iowa Status: Offline Points: 30894 |
Post Options
Thanks(0)
Quote Reply
Posted: May/23/2019 at 6:50am |
|
VERY possible someone added cruise to a non-cruise car, thus the location issues........
The parts can be found as many Eagles are getting scrapped and parted so the cables and other parts are out there. I have a couple of the cruise control boxes in case that happens to be the issue in this case. SUPER swamped today so haven't read the whole thing........... but I have Eagles in my shop now and all of he Eagle books so will try to pop back and look at this deeper later. |
|
|
|
|
73Gremlin401
Supporter of TheAMCForum
Joined: Mar/02/2013 Location: Stmbt Sprgs CO Status: Offline Points: 955 |
Post Options
Thanks(0)
Quote Reply
Posted: May/23/2019 at 8:38am |
|
The unit by the transfer case looks like a Terratrip Rally Computer speed transducer. This would be completely independent of a cruise control sender, and the location of it is about where Terratrip recommends mounting them. Do you know if your eagle was used either as a rally car, or in some other capacity like that? (FYI - this is where I mounted my Terratrip transducer in my 84 Eagle....)
|
|
|
73 Gremlin 401/5-spd.
77 Matador Wagon 360/727. 81 Jeep J10 LWB 360/4-spd 83 Concord DL 4-dr 258/auto  |
|
|
|
|
billd
Moderator Group
Forum Administrator Joined: Jun/27/2007 Location: Iowa Status: Offline Points: 30894 |
Post Options
Thanks(0)
Quote Reply
Posted: May/23/2019 at 8:54am |
Those aren't butt splices but are what I call "spade connectors" - the flat connectors, a male and a female. they allow quick disconnect and reconnect. But regardless, they should crimp, solder and heat shrink any connections like that exposed to elements or stress. Open connections gather moisture and corrode - leading to voltage drop and eventually loss of connection completely, unless a wire gets yanked out of the crimp-only connection before that happens. Looking again after a recent post - I do second-guess that being cruise at all........... as it likely wouldn't connect quite as this one did. The cruise sensor connections would take some doing to get connected like that. |
|
|
|
|
billd
Moderator Group
Forum Administrator Joined: Jun/27/2007 Location: Iowa Status: Offline Points: 30894 |
Post Options
Thanks(0)
Quote Reply
Posted: May/23/2019 at 10:40am |
|
OK, here are genuine AMC cruise control parts - some NOS, some well used, some sort of used.....
In this first photo, A is the speed sensor electric connector as it's supposed to be. B is the small side of the sensor that connects to the cable coming out of the cabin, through the firewall, FROM the speedometer HEAD in the dash. Note the sensor has two different size connections. Small goes toward the speedometer HEAD inside the car, large goes to the cable that comes from the transmission or transfer case.  A is firewall grommet, B is the end that goes to the speedometer HEAD inside, in the dash cluster and C is where the upper cable - the one to the speedometer HEAD - connects to the sensor.  Again, A to inside of car, into the cabin, to the speedometer, B connects to longer cable that comes up from the transmission or in the case of the Eagle, the transfer case. this sensor is only inches outside of the firewall up in the engine compartment in a normal factory installation. Note from these connectors - there's no way in ##@#$# to connect it directly to anything, let alone the speedometer gear in the transfer case - it has a female square for the cable to insert into and a large thread for a cable nut to screw onto. You would absolutely HAVE TO have a cable between the sensor and the speedometer drive gear.   |
|
|
|
|
Post Reply
|
|
Tweet
|
| Forum Jump | Forum Permissions You cannot post new topics in this forum You cannot reply to topics in this forum You cannot delete your posts in this forum You cannot edit your posts in this forum You cannot create polls in this forum You cannot vote in polls in this forum |
Click for TheAMCForum Rules
Topic Options
FSJunkie wrote: