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Slowly Working Through the Cruise Control

Old May 9, 2018 | 07:39 AM
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Default Slowly Working Through the Cruise Control

Yesterday began in earnest what seems to be a long and arduous process of repairing the cruise control system on my 95 D1.

So far, I've trimmed cracked hose ends and pulled and repair the CC vacuum pump.

This was super easy and i learned that it was stuck. i got it cleaned up and repaired then reinstalled. Apparently, moisture had seized the little motor. I rotated the shaft with some pliers then ran it a bit, all is well with the pump now.
Slowly Working Through the Cruise Control-snip_20180509071520.png Slowly Working Through the Cruise Control-20180508_172014.jpg

There is a very good write up on the procedure here: https://www.landyzone.co.uk/land-rov...repair.231884/

So now i am at the point of testing the ECM. using the pin check procedure as outlined in other posts on this forum, but im stuck. I cannot for the life of me, get the dang connector off the ECM, i can feel some sort of tab on either end of the connector, but they do not seem to move with pressure.

Is there a trick to removing the connector from the CC ECM?
 
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Old May 9, 2018 | 05:55 PM
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There is a small groove on the center of the metal clip, you need to push it in with a small flat screw driver that will cause the edges to open and then the plug can be pulled off. Give it a shot.
 
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Old May 9, 2018 | 06:55 PM
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Oh man. I'll need to get a bigger flashlight and the bifocals. I never saw a metal clip, only a black plug in a black socket.

I went through the troubleshooting steps, as outlined in the repairs sticky on this forum and the result is, I think, the variable speed sensor. I am getting a fairly constant 8.30-8.6 volts out. Voltage slightly decreases inversely with speed.

All else was good. So, i will do a litlle more research and expect to replace it. Then ill move on to the next problem.. driving from Kansas to Pennsylvania to Texas and back to Kansas in June, so I have some time to work. Also, thanks for the info on the metal clip. There are absolutely no good images on the ol web to guide me.
 
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Old May 9, 2018 | 08:57 PM
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So,, after reading more and thinking this through, i may have a bad ECU. My speedo is dead on, so i don't think it's the speed sensor, and the Rave diagram hints to a "speedometer speed output". is this something to be considered? Is this a component or just a "bent pipe" output from the transmission speed sensor? The Rave points only to the transmission speed sensor in the repair manual. I've googled the heck out of everything i can think of, but little comes up,
 
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Old May 10, 2018 | 06:04 AM
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Install a Disco 2 cruise control ECU, more reliable. It was the final piece of the puzzle for my inoperative cruise control.

https://landroverforums.com/forum/di...rol-ecu-57040/
 
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Old May 10, 2018 | 07:28 AM
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Thanks Matt,

I saw a thread on that, soldiering on the old connector to the D2 ECU, but i want to make sure all the peripheral parts are functioning before i do that. i may end up replacing the entire system before it works! I found the vacuum tubes all disconnected when i bought the truck, so someone had begun to troubleshoot. I still don't know if the 8.5v signal is a problem with the speedo output or the ECU.

Also, how hard was it to wire up the D2 ECU? did you use a 20 pin flat cable? im concerned about my brutish soldering skills.

johnny
 
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Old May 10, 2018 | 09:52 AM
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I purchased the D2 ECU with the intent of getting the cruise working on my D1, but other stuff has come up and I need to get back to it. The ECU I got has the connector and a bit of wire on it so I plan on hacking the old one apart and making my own adapter. That way it will plug in with either one I can find (if I need to)
 
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Old May 10, 2018 | 10:02 AM
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That is a great idea Jim. Is there a reason why folks are going to the D2 cruise ECU vs a D1? There are plenty of used D1 CC ECUs available with 60 day warranties. There must be a reason to go through the trouble.

If i dont get an answer about the voltages from the speedo output, i will have to tear out the gauges this weekend and may be in the market for a new ECU.
 
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Old May 10, 2018 | 06:03 PM
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After much groaning and gnashing of teeth, i finally found how to remove the CC ECU. For those in the future, here are photos of the retaining spring that holds the ECU in place. Near the junction of the ECU and plug, on the LH side, side you will see a small bit of metal wire. pry underneath. it will pop on the side you are prying. continue pying to the LH side of the vehicle till it comes off. the spring on mine sat too far deep to pry out from the ends and had to be lifted on the side.


Slowly Working Through the Cruise Control-20180510_174830.jpg

Slowly Working Through the Cruise Control-20180510_175115.jpg
 
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Old May 10, 2018 | 09:05 PM
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Help! I am now down to a sticking point. My CC ECU seems to beworking properly, but i cant run down where the speed signal is going wrong. my speedo is dead on, but the signal to the ECU is 8.5v, bouncing up and down.

 
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