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+--- Thread: Cruise control problems???? (/showthread.php?tid=1204)
Cruise control problems???? - 84300sd - 03-10-2010
hi yall, ive got an 84 300 sd w/ auto tranny. On occansion my cruise control will come on and the car will accelerate. the lever on the steering column will not turn it off but i can use decel/set lever to slow it down, but it will continue if i let off. Please let me know whats going on. thanks eric
RE: Cruise control problems???? - ForcedInduction - 03-10-2010
Could be either bad solder joints in the amp (common) or corroded contacts in the column switch.
RE: Cruise control problems???? - Alastair E - 03-10-2010
Just completely re-built my cruise-control amplifier and system...
But I believe your system has a different actuator to mine. I have a cylindrical vacuum actuator on the wheelhouse, I think yours is the electric motorised variety...
The 'ECU/amplifier works much the same, But the drive circuit to the throttle actuator is completely different.
Speed set, measurement comparators etc are much the same as is the MOSFET set-speed 'memory' circiut....
Your fault is most likely dry-joints on your ECU circuit-board. BUT BE very careful, and short-circuit the MOSFET connections before touching the board with an iron. The BSV81 Depletion-mode MOSFET is practically unobtainium and is VERY EASILY damaged easily by static Electricity
Speed/time errors (speed drops with time) will be the cap or the reed-relay block attached to the MOSFET flying-lead Gate connection....