John Morrison Posted January 3, 2022 Report Share Posted January 3, 2022 Hi all, HNY to everyone. Having tackled some oils leaks over the hols, which needed the H Frame etc removed, Now alll back, I have an issue. Switching the wipers on, immediately blows the fuse, Went looking and the rubber motor supports are shot, so disconnected the motor to see if it changed things, and it did not. Looking at the wiring diagram, this switch just closes to earth, yet every thing is fine until I give it a pull, If it just earths, and I have a dead short to earth, wouldn't that just mean that the motor would have run all the time? John. Quote Link to post Share on other sites
trchris Posted January 3, 2022 Report Share Posted January 3, 2022 Hi John The easiest way to track a short is to replace the fuse with a test light the light will glow to show a short allowing you to look for the problem without blowing any fuses hope this makes sense Chris Quote Link to post Share on other sites
Lebro Posted January 3, 2022 Report Share Posted January 3, 2022 Are you sure you have put the wires back where they came from ? other switches may be switching live 12V, if the wires are muddled up then your wiper switch could be grounding a live wire . Bob Quote Link to post Share on other sites
RogerH Posted January 3, 2022 Report Share Posted January 3, 2022 Hi John, removing the 'H' frame should not normally require removing wires etc from the wiper switch! So what did you do to the wiper switch when removing the 'H' frame. I assume you have a single speed motor. The switch should have two wire attached Black/Green and Black - there is no live to short to ground. Roger Quote Link to post Share on other sites
RobH Posted January 3, 2022 Report Share Posted January 3, 2022 (edited) If you electrically disconnected the motor and the fault remained John, it obviously isn't the motor itself. That leaves the loom and the switch. It is rather unlikely that the fault has suddenly appeared within the wiring loom. Most likely the non-earthed side of the wiper switch has somehow become connected to 'live'. As Bob says, the most likely thing is jumbled connections to the switch if those were disturbed during the work, or an inadvertent connection to 'live' by two adjacent spade connectors on the switches touching - or something like that. If you disconnect the green/black wire at the wiper motor and measure, there should be no voltage on it with ignition on. A resistance measurement to earth should show open-circuit until you operate the wiper switch. (If g/b is live, it will not cause the wiper motor to run) Edited January 3, 2022 by RobH Quote Link to post Share on other sites
tthomson Posted January 3, 2022 Report Share Posted January 3, 2022 (edited) I totally endorse the previous respondents. The motor is activated by grounding the green/black wire through the switch. Use a multimeter (or a 12volt bulb with one end to ground) to test things. Which fuse is blowing? If it is the one connected to green wires then disconnect the green wire at the motor which should prevent the problem, but won't fix the fault In most cases if a fuse blows, it is likely to be a wire connected to the wrong place, or less likely, some wire that is chafing and providing a short circuit. Good luck in solving it. It also occurred to me that a stalled and stuck wiper motor could also blow the fuse. so check that too. TT Edited January 3, 2022 by tthomson Quote Link to post Share on other sites
John Morrison Posted January 3, 2022 Author Report Share Posted January 3, 2022 Thanks Guys, not had achance to progress today. What is puzzling is that I was nowhere near the switches, when I pulled the H frame, I didn't even remove the radio. I did remove all three wires to the motor, thinking this will confirm a motor problem, but the fault remains, putting my thinking back onto the wiring. John. Quote Link to post Share on other sites
tthomson Posted January 4, 2022 Report Share Posted January 4, 2022 That would indicate to me that the green black wire is somehow shorting out to a live supply. With it disconnected from the motor, and with the wiper switch fully in (off) see if there is 12Volts on that wire. If so that is the problem, then trace back to find where the problem is happening. TT Quote Link to post Share on other sites
John Morrison Posted January 5, 2022 Author Report Share Posted January 5, 2022 Aj progress! Yes Tony I do have 12 v on that wire, so thank you for guiding me there. This means that this wire is collecting 12 v somewhere between the switch and the motor, and areas more likely than others? John. Quote Link to post Share on other sites
RobH Posted January 5, 2022 Report Share Posted January 5, 2022 (cough - see post no5) It is most likely this is a result of the work you did. Is it possible that wires have somehow become trapped or displaced? Was any part of the loom moved which might have dislodged a connection on the switches ? Quote Link to post Share on other sites
keith1948 Posted January 5, 2022 Report Share Posted January 5, 2022 (edited) 1 hour ago, John Morrison said: Aj progress! Yes Tony I do have 12 v on that wire, so thank you for guiding me there. This means that this wire is collecting 12 v somewhere between the switch and the motor, and areas more likely than others? John. Hello John I assume you are saying that you have 12 v on the wire at the switch with the other end of the wire disconnected from the wiper motor. If that is the case then I would suspect that the green wire that supplies power to the motor is shorting to the green/black inside the bit of the loom between the switch and the motor. This is the bit where the 2 wires run next to each other. Once you ground the switch you are effectively grounding the green wire and blowing the fuse. Connect a meter between the green/black wire at the switch or wiper end and connect the other end to the green wire at the motor end (with all wires disconnected from motor). If there is no resistance between the two or if the meter shows they are connected then that is the fault. The green wire should not connect to the green/black except via the motor. Keith p.s. mice in the car? Edited January 5, 2022 by keith1948 extra comment Quote Link to post Share on other sites
BRENDA1 Posted January 5, 2022 Report Share Posted January 5, 2022 John when I had a problem with my wipers I removed the switch and tested it local to the motor, motor found to be ok. Then tested the wiring found a fault in the wiring behind the glove box, had to remove to-get to the wires three wires had melted together, could not find a fault. Tested everything so now have a 8 block of fuses and relays under the passenger side. Hope you get sorted soon. Mike redrose group Quote Link to post Share on other sites
John Morrison Posted January 6, 2022 Author Report Share Posted January 6, 2022 Success! Job sorted and wipers fine. Following the advice here, its likely something I'd recently done, and being puzzled by the fact I had been know where near the switch, I retraced my actions, whilst, ahem, consulting the wiring diagram. I had an extra feed coming off the second terminal on the fan switch, thought I always had, anyway pulled this, and utilising Chris's brilliant tip about substituting a lamp for the fuse, pulled the wiper switch, no juice at the Black and Green, connected all up, and the motor spun away like a gun un. I'll go back now, and check everything else, whilst the car is still apart, but thanks to all, it would have taken me much longer, if ever, without the guidance. John. As a footnote, can anyone say why the electric washer circuit is not shown on any wiring diagrams, even though it was factory fit, as per the glovebox booklet? Quote Link to post Share on other sites
RogerH Posted January 6, 2022 Report Share Posted January 6, 2022 Hi John, even though the pump was factory fitted it wasn't standard. The standard was (I think) a manually operated push pump. Roger Quote Link to post Share on other sites
John Morrison Posted January 7, 2022 Author Report Share Posted January 7, 2022 Thanks Roger, might be so, but all the wiring diagrams, show an Overdrive option, so shouldn't the same apply? Anyhow anyone know where this windscreen washer switch might tap into the loom? John. Quote Link to post Share on other sites
RogerH Posted January 7, 2022 Report Share Posted January 7, 2022 1 hour ago, John Morrison said: Thanks Roger, might be so, but all the wiring diagrams, show an Overdrive option, so shouldn't the same apply? Anyhow anyone know where this windscreen washer switch might tap into the loom? John. Not necessarily. The OD was not an alternative as such- you either did or did not have it. The washer was a special alternative. The production line was geared up for the push pump. Roger Quote Link to post Share on other sites
stuart Posted January 7, 2022 Report Share Posted January 7, 2022 Washer pump can be fed from the fan motor green feed to the switch just piggy back it from the switch. Stuart. Quote Link to post Share on other sites
tthomson Posted January 12, 2022 Report Share Posted January 12, 2022 The attached diagram may help TT Quote Link to post Share on other sites
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