Category Archives: Renault Clock

Finding a leak that doesn’t exist, and a broken timepiece.

I’ve been having a hard time finding a few problematic issues with the Renault lately. Particularly it had started to leak power steering fluid quite badly, which would mark the floor where parked up and also get onto the auxiliary belt and make that slip.
Looking down from above, past the alternator and air conditioning compressor the pump looked rather wet, so I splashed out $14 and bought a full seal set for the pump. I decided to clean everything up with degreaser and refill the system, to hopefully see where the oil was leaking from.

dismantle

Begin by taking everything out, including battery, battery tray, moving the air conditioner comressor, remove the alternator and the brackets holding it all in.

empty

That leaves good access to the power steering pump. The corrugated plastic tube is the wiring for the front of the car, the braided hose is the gravity feed to the pump from the reservoir.

scrubbed up

Cleaned up the pump with an old toothbrush and engine degreaser. Rinsed it all down with warm water from the potato pump.

clean

Got a bit carried away as I had water left, so I cleaned down the inside of the hood where the oil had flicked off the belt, and the surrounding areas also. Topped up the oil and left it to dry overnight an in the sunshine.

full

Left it for two days, then checked on the level. Unfortunately the oil was all there still.

still oil

Another two days. Nope, there’s still all the oil left in there. The leak has miraculously fixed itself. Normally, hot, cold.. didn’t matter. It would leak regardless of it it was run or not. Now it’s not leaking!

clean pump

The pump is clean and dry, no signs of leakage.

oily frame

The only other place I can see is the return line, from the rack back up to the reservoir. If that has a crack or a pinhole it could be leaking. The engine cradle frame is a bit oily down under the back but I cannot see anything else that would be causing a leak. Further investigation to follow.

The second thing that irked me was the previously well-working clock had quit.

broken display

The display had taken to showing mostly nonsense, or nothing at all.

clock out

Took the dash to bits (again) and liberated the clock from the little cubbyhole it’s attached to.

polished

Cleaned up the smoked plastic section of the clock as it was all scratched and hazy.

components

Figured there were a couple pieces that might have failed and caused it to not work. Replaced the electrolytic capacitor and transistor. No joy.

circuit diagram

Followed the traces and built a diagram of what went where, to get a bit of an idea of how it all worked.

dead

Tested it but the chip was dead. No oscillator, just noise. The clock circuit boards are available, but they are a Jeep Wagoneer part, and as such suffer heavily from Jeep Tax and are therefore expensive.

zeroes

Upside-down image but poking power to the grid brought some nonsense up on the display so the VFD was all still good.

9

Poking about a bit more showed that some of the logic was alive, as various numbers could be liberated. Nothing sensible though.

led

Purchased a little LED clock with voltage and temperature capability for ten bucks, with the intention of fitting it into the clock as shown- looks OK but a little out of place and the very-bright display has no dimming capability.

dismantle

Decided to strip the board down and re-use the VFD, with the new clock module providing the logic. I’ve ordered a little 50V boost converter to drive the VFD, that will be proven to work first then I shall go ahead and get some high voltage transistors, pull the LED’s off the clock and use the output (multiplexed in the same way thankfully) to drive the VFD. Original clock, original display, just now with time, temperature and voltage display. Watch this space for updates.