Renault Scenic Relay Location

more likely a poor earth to the tailgate. add an earth wire and see if that fixes it.

They usually rely on the self parking switch in the motor too - ie the timer simply gives a short pulse and the self parking mechanism takes over to give the single sweep. And so on. However, with hatchbacks there's often an earth problem to the tailgate. So I'd first try running a bit of wire externally from the motor body to the body of the car and see if that fixes it. Or if you've got a DVM, set it to the 20 volt range and probe bare metal on the tailgate and body. With the wiper on, if there's an earth problem you'll see pulses of 12 volts where there should obviously be none.

Thanks for the replies so far, I'll try adding a wire later today. When I put my multimeter on it, will there be continuous pulses or just one every say ten seconds when it should sweep the windows. Would this be a problem with it being an intermittent fault? (ie do I have to stand there, however long it takes, waiting for the wiper to work?)

Cheers.

Ok, tried running an extra wire to the body of the car, no difference, tested with the multimeter and nothing. I also tested the wires (theres three of them) on the motor. One is live, one is pulsed, and the other is earth. At the plug the readings were, 11.6v, 11.6 pulsing to 0v. I also tested the earth for continuity to other places on the car and got good continuity readings. However, when I traced the wires from the plug to the motor the readings were all 0v. Does this mean the motor is knackered or has the intermittant fault? I tried bridging wires from the plug to the contacts on the motor but still no joy.

Any ideas Pete

If you mean that the readings go to zero when you connect the motor, then that shows a bad connection somewhere, usually if the wiring is hinged at the top of the tailgate that is where the fault will lie

Heh heh, told you I wasnt very good with cars. I'll try and explain again. On the motor there is a plug with three wires in. If I disconnect this plug and test the three wires against the bodies earth, I get readings of 11.6 permanent on one, 11.6 which drops to 0 every few seconds, and 0 which is the earth wire. If I test for continuity on the earth wire to the car body then I get a good reading so the earth is fine. However if I put the plug back in to the connector and follow the wires (2 inches max) then I get no readings whatsoever. The plug I get the readings on is a male type, this goes into a female connecter which is stuck to the motor, out of the female connector comes the wires which are then soldered onto the terminals on the motor. There is no readings on the soldered connections hence me trying to bridge the connections in case there was a problem with the plugs. This didnt alter anything. I hope that makes sense, if it doesnt I will try and get a photo tomorrow. Is there a way to test the motor on its own? Cheers Pete

The permanent power is the run/parking power, the pulse makes it move off the stop, then the permanent power takes over till the park position is reached, so powering the pulse one (with the earth connected) will make it run.

Like I said when the motor is connected you appear to have no volts? Shows a bad connection.

Yes, you can power up the motor separately, just take a 2 leads from the battery, put minus to the earth connector and plus to the one that is given a pulse. the motor should now run. If it does run then leave the earth wire connected and reconnect the power plug (turn on ign and wipers )and see what happens, if no result then try powering the pulse wire and using the plug earth, this should establish the fault.

of course if a completely separate earth and power won't run it then the motor is the problem.

Measuring voltages off load - ie with the motor unplugged - is pretty meaningless. A dirty connector (for example) further back could have such a high resistance as to stop the motor working - but the DVM has a *very* high input impedance so ignores this completely. So you need to probe for voltages with everything plugged in.