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Old 05-16-2009, 06:14 PM
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Join Date: Oct 2006
Location: Southern NJ
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Cruise Control Feedback Signal

My cruise on the '83 300D does not hold speed, but rather when engaging the cruise with the stalk, the cruise will engage take over the accelerator.
But, it is up to warp speed... It never levels off, just continues to increase speed. There is no hesitation and the resultant acceleration is steady. I must cut it off manually, both the stalk & brake will cut off the cruise.

Where is the speed feedback come from. I believe there is a signal generated within the speedo/instrument cluster. Is this the signal I am missing??

I have a line on a instrument cluster takeout and was thinking of getting the cruise operating once again.

Thanks,
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Experience is something you get, Just after you needed it....
'99 E300 295K, '83 300D 220K, '75 240D 185K sold
'80 MCI Bus Conv DD 6V92TA, w/4 cyl. Kubota diesel GenSet 12.5KW
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  #2  
Old 05-16-2009, 07:00 PM
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Quote:
Originally Posted by cessna5354 View Post
My cruise on the '83 300D does not hold speed, but rather when engaging the cruise with the stalk, the cruise will engage take over the accelerator.
But, it is up to warp speed... It never levels off, just continues to increase speed. There is no hesitation and the resultant acceleration is steady. I must cut it off manually, both the stalk & brake will cut off the cruise.
If your speedometer needle is steady (you have a new cable or your cable is properly lubed), then I believe the mostly likely caused is by a faulty cruise amplifier.
Or the cruise actuator is worn at a certain speed and it is searching/hunting for a better contact point. As shown in this pic.

http://www.gdl-online.com/act_boards.html



Quote:
Originally Posted by cessna5354 View Post
Where is the speed feedback come from. I believe there is a signal generated within the speedo/instrument cluster. Is this the signal I am missing??

I have a line on a instrument cluster takeout and was thinking of getting the cruise operating once again.
...
Here is a shot of the speed sensor, the black box in the back of the cluster.

I don't think you need a whole new cluster. But there is a possibility the speed sensor could go bad.


Here are some helpful links in Dx it.

http://userweb.windwireless.net/~jimc/mamerepairs.html (look for the cruise control section.)

http://gdl-online.com/test024.html
'
Attached Thumbnails
Cruise Control Feedback Signal-cruiseactuatorwornboard.jpg   Cruise Control Feedback Signal-clusterspeedsensor.jpg  
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Last edited by DeliveryValve; 05-16-2009 at 07:05 PM.
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Old 05-16-2009, 08:24 PM
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Join Date: Oct 2006
Location: Southern NJ
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Delivery Valve,

Thanks for the info, When my cruise is engaged, it is quite firm and very steady in its acceleration. I can engage @ 40 mph and it will accel, right up and thru 75mph. No hunting, hesitation, or anything other than a steady acceleration. My speedo needle is very steady as well.
I know many times the amp is the culprit. Maybe I should scoop the amp, and instrument cluster. I should p/u the tach amp as well.

I have pulled my instrument cluster, but I never inspected the "wipe" areas of the circuit board. Possibly the job for next weekend.

Thanks,
__________________
Gary
Experience is something you get, Just after you needed it....
'99 E300 295K, '83 300D 220K, '75 240D 185K sold
'80 MCI Bus Conv DD 6V92TA, w/4 cyl. Kubota diesel GenSet 12.5KW
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