Re: Getting OGU roadworthy again
Posted: Sun Jun 02, 2013 3:27 pm
I booked in for an MOT test on Monday morning (tomorrow) and on Saturday was clearing out the tools & accumulated rubbish from the passenger space, when I realised that I had not actually tested the brake lights. Tricky to do on one's own.
So I used a broom handle to push the brake pedal and had closed the garage door so that I could see the red glow. To my horror the brake lights were not working, but it was too late on Saturday to do much.
So up bright & early today. Visions of a dead brake pressure switch, not obtainable in an instant; thoughts of how I could rig a mechanical switch on the brake pedal from bits & pieces around.
Ran it up on ramps balanced a long mirror against some bricks behind the car so that I could see the brake lights from under the car & crawled underneath with a multi-meter, pulled the wires off the brake pressure switch & checked; there was 12v to chassis on one of the wires, good ho.
Made up a short wire with two spade connectors to join the disconnected wires, in place of the pressure switch. No brake lights on at first, but shortly after due to a bit of wiggling of the wire, I could see that they came on... Hooray... diagnosis = dirty contacts on the switch and its connectors.
So brass wire brush & a bit of sandpaper & a pliers to squeeze the slide on connectors a bit tighter.
But could the brake pressure switch be broken also as an open circuit? .. Moved the mirror to approx 45 degree angle so that I can see the lights while pressing the brake pedal with my foot. ... Bingo all working fine.
Ready for MOT test tomorrow.
So I used a broom handle to push the brake pedal and had closed the garage door so that I could see the red glow. To my horror the brake lights were not working, but it was too late on Saturday to do much.
So up bright & early today. Visions of a dead brake pressure switch, not obtainable in an instant; thoughts of how I could rig a mechanical switch on the brake pedal from bits & pieces around.
Ran it up on ramps balanced a long mirror against some bricks behind the car so that I could see the brake lights from under the car & crawled underneath with a multi-meter, pulled the wires off the brake pressure switch & checked; there was 12v to chassis on one of the wires, good ho.
Made up a short wire with two spade connectors to join the disconnected wires, in place of the pressure switch. No brake lights on at first, but shortly after due to a bit of wiggling of the wire, I could see that they came on... Hooray... diagnosis = dirty contacts on the switch and its connectors.
So brass wire brush & a bit of sandpaper & a pliers to squeeze the slide on connectors a bit tighter.
But could the brake pressure switch be broken also as an open circuit? .. Moved the mirror to approx 45 degree angle so that I can see the lights while pressing the brake pedal with my foot. ... Bingo all working fine.
Ready for MOT test tomorrow.