Corkery11 Posted June 7, 2023 Report Share Posted June 7, 2023 After trawling the net for an answer I'm no closer to sorting the wiper. Thanks to various pointers on the forum the last few days most of the loom is wired up and thanks to suggestions regarding putting headlight bulbs and increasing the thickness of cabling as I link up the battery I have even managed to retain all the special smoke within the loom. However ... The wiper is costing me an arm and a leg in fuses. I've just sent off for 200 so as you can see pessimism is the order of the day. I think if you understand electrics this may well be an obvious issue but as I don't it isn't. There is a green and a green and black wire running to the switch. Motor has an earth to the mount with a nice new copper washer and there is a black (,earth?) Going to the bolt marked E Middle / 2 slotted spade marked E is green wire. Bottom / 1 is wired green and black. In this configuration it does not turn on with the switch. If I remove the green wires and attach a Powerprobe supplying negative to 1 and positive to 2 the motor runs fine. After running like this if I try to use the cars switch again the motor will run for a second os so as it goes through its self park routine. With ignition off both terminals on the switch show negative. With switch and ignition on both show positive. Likewise the two green, green and black show positive on the females whilst on the appropriate spade connections. The brown wire on the self park also shows as positive and both earth's still negative. If I randomly move the "cap" for the self park the motor will also kick in for a second or so. I have put alignment marks on the body and cap so that they should be it the correct place but was anticipating having to fiddle with this more when the car was back together if necessary. Quote Link to post Share on other sites
Corkery11 Posted June 7, 2023 Author Report Share Posted June 7, 2023 Quote Link to post Share on other sites
Corkery11 Posted June 7, 2023 Author Report Share Posted June 7, 2023 Quote Link to post Share on other sites
stuart Posted June 7, 2023 Report Share Posted June 7, 2023 You should have green and black to one side of the switch and the other side should be black going to earth on the instrument panel. At the motor the green should have 12 volts with ignition on and the black and green goes to the switch.. Stuart. Quote Link to post Share on other sites
BlueTR3A-5EKT Posted June 7, 2023 Report Share Posted June 7, 2023 8 minutes ago, stuart said: You should have green and black to one side of the switch and the other side should be black going to earth on the instrument panel. At the motor the green should have 12 volts with ignition on and the black and green goes to the switch.. Stuart. Beat me to it Stuart Plus the motor casing end plate must be earthed if you expect the motor to self park. Which is how you have wired it. But check the continuity of the motor to earth Quote Link to post Share on other sites
Corkery11 Posted June 7, 2023 Author Report Share Posted June 7, 2023 Thanks for the replies but I think I've misunderstood somewhere along the line. Stuart by Green and Black to one side of the switch do you mean both the Green wire and the Green and black wire go to one (same) terminal and an earth wire goes to the other terminal? I gave this a go but had another fuse pop so presume I've got the wrong end of the stick. Think the earth cables that were mentioned are ok but not quite sure what / how to check motor continuity to earth. By "not quite" I mean "no idea". If I attach the Powerprobe to the two earth terminals or any unpaired metal part of the casing I'm getting confirmation of Earth. Does that indicate continuity? Ta Mark Quote Link to post Share on other sites
Corkery11 Posted June 7, 2023 Author Report Share Posted June 7, 2023 Forgot to say my wiring diagram shows a different setup for the switch and wiring at the motor but I understand that is for the earlier car? Quote Link to post Share on other sites
RobH Posted June 7, 2023 Report Share Posted June 7, 2023 (edited) Just to clarify the above: The green wire is ignition switched 12V and goes direct to the motor, that means there should only be power on that lead when the ignition is on. The green/black wire goes from the motor to the wiper switch and the other side of the switch goes to earth. There should never be 12V on that wire when disconnected. If you connect it to the motor with the wipers off and ignition on, it will register 12V as that is coming through the motor from the green wire. The brown wire for the self-park also picks up power from the green wire and will show 12V when the motor is parked and the ignition is on . Edited June 7, 2023 by RobH Quote Link to post Share on other sites
stuart Posted June 7, 2023 Report Share Posted June 7, 2023 (edited) 14 minutes ago, Corkery11 said: Forgot to say my wiring diagram shows a different setup for the switch and wiring at the motor but I understand that is for the earlier car? Yes but same principle applies, the switch just earths the supply for the motor. Your extra green that you have at the switch doesnt go there. All you have at the switch is as stated above. Green and black one side of the switch and then a short piece of black from the other side of the switch to the earth terminal at the back of the centre instrument panel. The earth cable on the motor must have continuity to the body as sometimes when youve painted the body that bolt may not earth right through. Easy to check using the continuity setting on your meter. Probably the one that goes beep. Edit; Rob beat me too it! Stuart. Edited June 7, 2023 by stuart Quote Link to post Share on other sites
stuart Posted June 7, 2023 Report Share Posted June 7, 2023 That extra green you have maybe for heater blower if fitted. If not and its not required for anything else then tape it off and make it safe as its ign controlled 12v. Stuart. Quote Link to post Share on other sites
BlueTR3A-5EKT Posted June 7, 2023 Report Share Posted June 7, 2023 You are using the wrong wiring diagram. The one you have is for TR2/3 with non self parking CRT type wiper motor. Quote Link to post Share on other sites
Corkery11 Posted June 7, 2023 Author Report Share Posted June 7, 2023 Bloody hell fellas! Thank you so much for that, got a whirring motor now. That has made my day. Mark Quote Link to post Share on other sites
stuart Posted June 7, 2023 Report Share Posted June 7, 2023 3 minutes ago, Corkery11 said: Bloody hell fellas! Thank you so much for that, got a whirring motor now. That has made my day. Mark Dont forget to set the park before fitting wiper arms! Stuart. Quote Link to post Share on other sites
Corkery11 Posted June 7, 2023 Author Report Share Posted June 7, 2023 12 minutes ago, stuart said: That extra green you have maybe for heater blower if fitted. If not and its not required for anything else then tape it off and make it safe as its ign controlled 12v. Stuart. Thanks, I'm on with it now. When I dug it out of the wiper and traced it back it's at the fuel gauge. I've a horrible feeling I added it myself going from my wiring diagram. Thankfully BlueTr3a has given me a touch more insight regarding my diagram. Thanks again you lot Quote Link to post Share on other sites
Corkery11 Posted June 7, 2023 Author Report Share Posted June 7, 2023 1 minute ago, stuart said: Dont forget to set the park before fitting wiper arms! Stuart. Hi Stuart taped a big hunk of masking tape on spindles to remind me. Car is covered in tie wraps to remind me of various nuts and bolts needing final tightening once it's loaded up and down in it's wheels. I'd like to claim it's an age thing but I've always had a lousy memory. Quote Link to post Share on other sites
BlueTR3A-5EKT Posted June 7, 2023 Report Share Posted June 7, 2023 36 minutes ago, Corkery11 said: Thanks, I'm on with it now. When I dug it out of the wiper and traced it back it's at the fuel gauge. I've a horrible feeling I added it myself going from my wiring diagram. Thankfully BlueTr3a has given me a touch more insight regarding my diagram. Thanks again you lot Sorry I cannot post a wiring diagram but I am in a TR desert sipping wine and eating cheese Quote Link to post Share on other sites
Corkery11 Posted June 7, 2023 Author Report Share Posted June 7, 2023 Good wine and good cheese? Actually bad wine and bad cheese is still a good combo. Quote Link to post Share on other sites
BlueTR3A-5EKT Posted June 7, 2023 Report Share Posted June 7, 2023 Yes wine and cheese specially selected for their qualities Quote Link to post Share on other sites
markaluge Posted June 7, 2023 Report Share Posted June 7, 2023 It was great to see this thread as I am in the garage with the instrument panel out trying to get my wipers and fuel gauge to work. From the comments above I think I should have a green/black going to one side of the switch and a black earth on the other side. Thing is the wiring loom came with a fitted ring on the green/black (1) which I am reluctant to cut off unless sure that is the right thing to do. I then have a green which splits into 2 with a ring connector on one side (2) and nothing on the other (5). There is then an earth for the fuel gauge which has a spade connector (3) and another with a ring connector which I think goes to earth at the dash fitting screw (4). What goes where please and how do I confirm that the sender unit in the tank is sending a reading? Mark (never wanted to be a vehicle electrician) Quote Link to post Share on other sites
Corkery11 Posted June 7, 2023 Author Report Share Posted June 7, 2023 8 minutes ago, markaluge said: It was great to see this thread as I am in the garage with the instrument panel out trying to get my wipers and fuel gauge to work. From the comments above I think I should have a green/black going to one side of the switch and a black earth on the other side. Thing is the wiring loom came with a fitted ring on the green/black (1) which I am reluctant to cut off unless sure that is the right thing to do. I then have a green which splits into 2 with a ring connector on one side (2) and nothing on the other (5). There is then an earth for the fuel gauge which has a spade connector (3) and another with a ring connector which I think goes to earth at the dash fitting screw (4). What goes where please and how do I confirm that the sender unit in the tank is sending a reading? Mark (never wanted to be a vehicle electrician) Hi Mark as you will no doubt realise I'm the last person to give electrical advice but I can tell you I had to snip off numerous spade terminals and ring terminals to get things to fit. My switches etc had the screw type terminals. Cheers, from one Mark to another Quote Link to post Share on other sites
Corkery11 Posted June 7, 2023 Author Report Share Posted June 7, 2023 One of the mods I have made to the car was as a result of making up a replacement battery box. The big hole in the bulkhead looked great for future access behind the dash as wiring up the panel while pushing cable in and out seemed like a recipe for error. As a result I framed up / strengthened / tapped the hole with welded up plate and now I can remove the battery box if needed. I'm hoping this doesn't turn the car into jelly. To be honest it hasn't made things a hole (sorry) lot easier regards the wiring as I have a heater but without a heater I think it might have been a little more useful. I did find it handy for setting up / installing the air vent. Quote Link to post Share on other sites
RobH Posted June 7, 2023 Report Share Posted June 7, 2023 (edited) 1 hour ago, markaluge said: What goes where please and how do I confirm that the sender unit in the tank is sending a reading? 1 and 2 look as though they are intended to be either side of an instrument and the Advance Autowire schematic for a TR3 has those colours to the fuel gauge with the spare green feed (5) going to the wiper switch. That arrangement is for the early wiper motor though. There is room for confusion here, as the fuel gauge has a green wire with a black stripe while the wiper motor has a black wire with a green stripe . To be on the safe side you really need to trace that through to ensure you have it right. This is how it is probably intended to be with that loom - the numbers correspond to those on your picture: If you have the later wiper motor this will not work. To check whether the tank sender is working you need to measure the resistance from the green/black wire to earth. If you can arrange to lift the float arm using a wire down the filler pipe, the resistance should vary with the arm position. Edited June 7, 2023 by RobH typo Quote Link to post Share on other sites
markaluge Posted June 7, 2023 Report Share Posted June 7, 2023 I should add that there is another wire connected to the wiper switch which looks to be black but maybe it is my poor eyesight and that is the black/green, in which case I may have had things right and it is the earthing which is my problem! The back of the fuel gauge is marked ‘T’ and ‘B’, I’m thinking it must made a difference which way around I connect it up. Quote Link to post Share on other sites
Lebro Posted June 7, 2023 Report Share Posted June 7, 2023 On the fuel gauge "T" goes to the tank sender unit, & "B" goes to switched 12V (green wire) Also the body of the gauge (& the sender unit) must have good earth connections. Bob Quote Link to post Share on other sites
markaluge Posted June 8, 2023 Report Share Posted June 8, 2023 10 hours ago, Lebro said: On the fuel gauge "T" goes to the tank sender unit, & "B" goes to switched 12V (green wire) Also the body of the gauge (& the sender unit) must have good earth connections. Bob Thanks Bob, I will have another go at it this evening. Spare fuzes at the ready!! Quote Link to post Share on other sites
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