I was driving to church one Sunday evening in heavy traffic. When I came a few driveways before the church's parking lot, I activated my turn signal, applied the brakes, and turned into the parking lot. I was startled to hear a horn blow from the car behind me. It was odd that I hear any horn in my city, other than a general chorus of car alarms that go off on windy days.
When the service ended, I went out and put my foot on the brake. It was dark, so I would have been able to see the brake lights glowing. But there was a problem -- no lights. I got down on the floor and pushed the brake switch with my fingers. The tail lights lit up like a Christmas tree. But when I pushed the pedal, no lights.
I drove home (carefully) and disassembled the assembly. With my ohm meter I measured and found it working with minimal resistance. I grounded the brake wires and found the lights were working. I put it back together and again found that they did not light up.
It turns out that the switch was bad, but only when pushed at the right angle and with the right pressure all while mounted in the brake pedal frame. A $20 switch at the dealer solved the problem.
This entry was submitted by John Bate and edited by Jennifer Campbell.
John Bate has been a system engineer at Volvo Trucks since 1999, working with electrical harness design and process improvement. His background includes embedded computers and software, HF radio design, telematics, and writing copious amounts of simulation models and processes improvement software.
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