Cruise Control Help
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Instructor
Joined: Mar 2007
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Cruise Control Help
for some reason my cruise works perfectly along flat roads, but if I hit bumps or shakes in the road, the cruise will disengage for a slit second and then resume when the road is flat again.
And ideas? I like my cruise for long trips...
cheers!
And ideas? I like my cruise for long trips...
cheers!
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Joined: Jul 2003
Posts: 2,577
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From: Atlanta
German electronics are notorious for cold solder joints. The plug-in connections are usually pretty good, but if someone did not push a plug together properly there can be intermittent contact. An easy fix is to clean and tighten all the electrical connections in the system (Radio Shack sells electrical contact cleaner that works great). Be sure to clean and tighten any grounds as well.
Probably the real problem, but more skill required: open the cruise amplifier, and look at each solder joint under a microscope. The solder beads should be glossy and appear to wick to the wire. If you see a discontinuity where the solder touches the wire, that is a cold joint. Remove the solder blob with a solder sucker, and reapply a good rosin-core electronic solder.
Probably the real problem, but more skill required: open the cruise amplifier, and look at each solder joint under a microscope. The solder beads should be glossy and appear to wick to the wire. If you see a discontinuity where the solder touches the wire, that is a cold joint. Remove the solder blob with a solder sucker, and reapply a good rosin-core electronic solder.
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Joined: Jan 2007
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From: Concord NC
Might be possible the switch on the clutch pedal needs to be adjusted. Maybe when you hit a bump the pedal moves enough to disengage it for a minute. My cruise will disengage when I press the clutch and engage again when I let it back out. Just a thought and would be easy to check.
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Joined: Jul 2003
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From: Atlanta
The service manual has the location of every connector. The cruise amp is located below the passenger seat and pretty easy to take out for a bench inspection. The cruise actuator is on the throttle assembly at the top of the engine, and difficult to find unless you know what it looks like. If you have zero experience, it is probably wise to get some help from someone that is familiar with electronic troubleshooting.
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Joined: Apr 2006
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From: The 909, CA
Might be possible the switch on the clutch pedal needs to be adjusted. Maybe when you hit a bump the pedal moves enough to disengage it for a minute. My cruise will disengage when I press the clutch and engage again when I let it back out. Just a thought and would be easy to check.
Check this first before you go after the solder joints since its the easiest to do. I had similar erratic cruise control functionality and adjusting the cruise microswitch solved it.
elbeee964 had a similar issue that was a result of a weak clutch slave unit not bringing the clutch pedal back up fully even though his switch was properly adjusted. Thread HERE