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PKRWUD · 11-06-2001, 07:38 AM

Reminds me (very little) of a customer I had once. He had a newer F150, and came in complaining that his cruise control never worked at night. He said it worked fine during the day, but as soon as it got dark outside, it wouldn't work. That's all I had to go on. I checked everything, and went on several test drives, and everything worked fine for me. I talked him into leaving it overnight so I could test drive it in the dark, and it worked fine for me then, too. I returned it to him telling him I could find nothing wrong, and off he went. He returned the next day, saying the problem was still there. I asked him to come by that evening so that he could show me the problem occuring. We went for a drive, and sure enough, the cruise control wouldn't work. I noticed, though, that when he turned on the headlights, he also turned on some fog lights that he had added. I asked him to turn the fog lights off, and try again, and the cruise control worked fine. He dropped off the truck the next day, and I fixed it for him.

What had happened was that when he installed the fog lights, he wired the power for them into the brake light circuit. Every time he turned them on, the body computer noticed the demand in the brake light circuit, and mistook that as him applying the brakes, which always turns off the cruise control. I rewired the power supply to the fog lights, and all was fine.

I know this has nothing to do with this post, but it's a good FYI.

Take care,
-Chris

------------------
Retired Moderator
MustangNet

My site: Peckerwoods Pit Stop

My teams site: Jim Porter Racing

RACECAR spelled backwards is RACECAR

HEY !!! Are you ASE Certified ??? If you are, ask me about iATN.

11-06-2001, 07:38 AM	#5
PKRWUD Junior Member Join Date: Mar 1999 Location: Ventura, California Posts: 8,981	Reminds me (very little) of a customer I had once. He had a newer F150, and came in complaining that his cruise control never worked at night. He said it worked fine during the day, but as soon as it got dark outside, it wouldn't work. That's all I had to go on. I checked everything, and went on several test drives, and everything worked fine for me. I talked him into leaving it overnight so I could test drive it in the dark, and it worked fine for me then, too. I returned it to him telling him I could find nothing wrong, and off he went. He returned the next day, saying the problem was still there. I asked him to come by that evening so that he could show me the problem occuring. We went for a drive, and sure enough, the cruise control wouldn't work. I noticed, though, that when he turned on the headlights, he also turned on some fog lights that he had added. I asked him to turn the fog lights off, and try again, and the cruise control worked fine. He dropped off the truck the next day, and I fixed it for him. What had happened was that when he installed the fog lights, he wired the power for them into the brake light circuit. Every time he turned them on, the body computer noticed the demand in the brake light circuit, and mistook that as him applying the brakes, which always turns off the cruise control. I rewired the power supply to the fog lights, and all was fine. I know this has nothing to do with this post, but it's a good FYI. Take care, -Chris ------------------ Retired Moderator MustangNet My site: Peckerwoods Pit Stop My teams site: Jim Porter Racing RACECAR spelled backwards is RACECAR HEY !!! Are you ASE Certified ??? If you are, ask me about iATN.