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Check your brake switch. Is your CC electronic or vacuum? I cannot remember what year they switched over. My '91 is vacuum.
1993 was the first year for the electronic Speed Control system on these trucks. There should be two mechanisms in place to disengage the Speed Control, the Brake On/Off (BOO) switch (located on the brake pedal assembly) and the Brake Pressure Switch (BPS) located near the RABS hydraulic module on the driver side frame rail. Very odd if both failed. I hope the Speed Control recall has been performed on the OP's vehicle. If not, it's a fire waiting to happen.
The BOO may indeed be bad, but the Brake Pressure Switch (BPS) is the backup. So now the OP most likely has two failed circuits, with one of them a well known fire hazard.
The BOO may indeed be bad, but the Brake Pressure Switch (BPS) is the backup. So now the OP most likely has two failed circuits, with one of them a well known fire hazard.
Can you enlighten me on this fire hazard thing? My cruise control is just decoration right now, but I would like to fix it someday.
Can you enlighten me on this fire hazard thing? My cruise control is just decoration right now, but I would like to fix it someday.
This happened relatively recently to member on this forum. Found it: She's Gone...
If you read through that thread it appears the Recall was performed....but the first version was wired wrong which still allowed power even with the key in the OFF position.
Short story: The Brake Pressure Switch is prone to rupturing the membrane between the brake fluid and the switch mechanism. To pile onto this flaw the power for the BPS is on anytime the battery is connected. Therefore when this membrane ruptures it allows power to conduct through the brake fluid which in turn is flammable when heated enough...which actually happens. The recall involved changing the BPS power feed to a circuit that is "hot" only when the key is in the Run position. IF there were signs of a leaking BPS it was changed. IF NOT, they left the existing BPS in place. The latter is a bad idea IMHO.
If your truck does not have the add-on power harness for the BPS: DISCONNECT THE WIRING TO THE BPS NOW!
For 1994 and up F-series trucks look for this add-on harness: courtesy of Subford
1993 F-series trucks the BPS is located near the RABS hydraulic module mounted on the driver side frame rail. Literally under the driver's left foot.There should be the same add-on recall harness in place.
