Supahonky Posted August 23 Share Posted August 23 Alright on to the next… anybody have any schematics for the high been circuit and the washer fluid motor circuit?? I’m having a hard time finding such diagrams aswell as a diagram for the relay/beakers 1989 r688st Quote Link to comment https://www.bigmacktrucks.com/topic/74492-r-model-electrical-help/ Share on other sites More sharing options...
Supahonky Posted August 23 Author Share Posted August 23 For some reason it won’t let me upload a picture of the breakers and relays Quote Link to comment https://www.bigmacktrucks.com/topic/74492-r-model-electrical-help/#findComment-557480 Share on other sites More sharing options...
mowerman Posted August 23 Share Posted August 23 sorry nothing this time,,,manuals go back to 83,,, good luck..bob Quote Link to comment https://www.bigmacktrucks.com/topic/74492-r-model-electrical-help/#findComment-557481 Share on other sites More sharing options...
Supahonky Posted August 23 Author Share Posted August 23 It’s an 1989 so shouldn’t there be a manual then? Quote Link to comment https://www.bigmacktrucks.com/topic/74492-r-model-electrical-help/#findComment-557484 Share on other sites More sharing options...
mowerman Posted August 23 Share Posted August 23 Yes, not sure if you could find one online but Mack trucks. I’m sure has them. They are not cheap. You might try Amazon first. It’s amazing what those guys carry that’s what I would do first good luck. Quote Link to comment https://www.bigmacktrucks.com/topic/74492-r-model-electrical-help/#findComment-557514 Share on other sites More sharing options...
mowerman Posted August 23 Share Posted August 23 Well, I don’t know if this will help you there’s a bunch of them for sale. eBay good luck as I mentioned. They are very expensive even secondhand. Quote Link to comment https://www.bigmacktrucks.com/topic/74492-r-model-electrical-help/#findComment-557515 Share on other sites More sharing options...
Joey Mack Posted August 23 Share Posted August 23 Honky,, I tried to find the diagrams but failed. What exactly are you needing to fix? the washer motor is in the right door with the tank. and you have a wiper knob in the dash that you push to wash.. i'm sure you can use a DVOM, set to ohms to find the circuit from the switch to the wiper fuse, and from the fuse to the pump.. Sorry I dont have better info. Quote Link to comment https://www.bigmacktrucks.com/topic/74492-r-model-electrical-help/#findComment-557516 Share on other sites More sharing options...
mowerman Posted August 23 Share Posted August 23 Ha ha Joey you still got me beat. I guess I didn’t notice he’s just having trouble with windshield washer. It’s probably just a faulty pump. They don’t last forever. 1 Quote Link to comment https://www.bigmacktrucks.com/topic/74492-r-model-electrical-help/#findComment-557518 Share on other sites More sharing options...
mowerman Posted August 23 Share Posted August 23 Got new doors off of UPS F model years ago for my DM. The passenger side has the hole for it…. Bob Quote Link to comment https://www.bigmacktrucks.com/topic/74492-r-model-electrical-help/#findComment-557519 Share on other sites More sharing options...
Joey Mack Posted August 23 Share Posted August 23 yep,, I struggle with correct answers when someone wants a wiring diagram for an 80's 'R' model.. I have worked on many of them, and have just followed the wires.. the arrangement is simple compared to the crap we have had during recent decades. i expect that the only wires in his right side door are for heated/moto mirror and the washer pump.. too bad the fuse panel diagrams are hard to find.. 1 Quote Link to comment https://www.bigmacktrucks.com/topic/74492-r-model-electrical-help/#findComment-557520 Share on other sites More sharing options...
Supahonky Posted August 25 Author Share Posted August 25 The main thing I’m struggling with is a diagram of all the breakers and the couple relays it would save me lots of time. I found the tank and pump already someone sawzaw’d a flap to access it haha. I’d like to try and maintain the original look but the breaker panel isn’t marked at all I’d hate to just have to run new wires for everything Quote Link to comment https://www.bigmacktrucks.com/topic/74492-r-model-electrical-help/#findComment-557575 Share on other sites More sharing options...
Joey Mack Posted August 25 Share Posted August 25 if i remeber right the fuses and such had sticker type labels.. I went to Mack E-Media the other day to try to find it for you, and I failed.. I dont have diagrams for your truck either.. I'm sorry, this sucks.. Jojo Quote Link to comment https://www.bigmacktrucks.com/topic/74492-r-model-electrical-help/#findComment-557576 Share on other sites More sharing options...
mackey58 Posted August 25 Share Posted August 25 Maybe mack museum Quote Link to comment https://www.bigmacktrucks.com/topic/74492-r-model-electrical-help/#findComment-557577 Share on other sites More sharing options...
mackey58 Posted August 25 Share Posted August 25 They sent me the wiring diagram for the 90 RD690S. Would the glove box diagram help or would it be different. Mack museum will take awhile 1 Quote Link to comment https://www.bigmacktrucks.com/topic/74492-r-model-electrical-help/#findComment-557578 Share on other sites More sharing options...
Supahonky Posted August 25 Author Share Posted August 25 Please post anything you have and I’ll see if it relates. I keep trying to post a picture of the breakers and relays but it won’t post? I’ve posted other pictures no problem. it’s crazy I can’t find info for this truck but my 67 Chevy which is way older I have unlimited information available Quote Link to comment https://www.bigmacktrucks.com/topic/74492-r-model-electrical-help/#findComment-557581 Share on other sites More sharing options...
Supahonky Posted August 25 Author Share Posted August 25 (edited) IMG_7233.HEIC ok hopefully this works now… here’s what I have for breakers/relays Edited August 25 by Supahonky Quote Link to comment https://www.bigmacktrucks.com/topic/74492-r-model-electrical-help/#findComment-557582 Share on other sites More sharing options...
Joey Mack Posted August 25 Share Posted August 25 very good picture. the flasher relay rigging is common, I sugest making #10 wire harness to neaten that up and lower the rish of shorting. There is a pre-made flasher harness for sale as well. I will look at my books in a bit, and see what I have.. Quote Link to comment https://www.bigmacktrucks.com/topic/74492-r-model-electrical-help/#findComment-557591 Share on other sites More sharing options...
Joey Mack Posted August 25 Share Posted August 25 https://photos.app.goo.gl/bJjU3auKcasfzjMAA Here is what I have, I sure hope it helps... If you dont have that book, see if one is on E-Bay.. It has a ton of useful info.. Jojo 1 Quote Link to comment https://www.bigmacktrucks.com/topic/74492-r-model-electrical-help/#findComment-557592 Share on other sites More sharing options...
Supahonky Posted August 25 Author Share Posted August 25 Thanks Jojo, how does the sequence go for these panels I tried left to right in ascending numbers but the breaker amps don’t match. Quote Link to comment https://www.bigmacktrucks.com/topic/74492-r-model-electrical-help/#findComment-557594 Share on other sites More sharing options...
Joey Mack Posted August 25 Share Posted August 25 Left to right,, I was hoping there were some markings still left in the panel. The charts are not laid out like you would see in todays diagrams.. Sorry that I dont have a copy of the papers that would have been tucked in the fuse door pocket.. You may have to turn everything 'on' in the truck and pull the breakers one at a time to see what shuts off. at least you dont have 30 of them, only 12.. I'm tryin' bud.. Quote Link to comment https://www.bigmacktrucks.com/topic/74492-r-model-electrical-help/#findComment-557595 Share on other sites More sharing options...
Vladislav Posted August 25 Share Posted August 25 For more than 10 years I kept my eyes open for such the diagram, My truck is 1988 (1989 model year) R688. And I didn't have any luck. There's a "R-model wiring diagram" as a black and white electric scheme you can find on this site or elsewhere on the net. But that one is for earlier year's R's and doesn't correspond much to what you have in your truck. Quote Никогда не бывает слишком много грузовиков! leversole 11.2012 Link to comment https://www.bigmacktrucks.com/topic/74492-r-model-electrical-help/#findComment-557600 Share on other sites More sharing options...
Joey Mack Posted August 26 Share Posted August 26 Any Luck ?? Quote Link to comment https://www.bigmacktrucks.com/topic/74492-r-model-electrical-help/#findComment-557654 Share on other sites More sharing options...
Supahonky Posted August 27 Author Share Posted August 27 Not yet I’ve chased down all wires one for the high beam(brown and white I think) on the power buss on the passenger side by headlight was disconnected but nothing. The new switch has power but I can’t get it to send juice to where ever it needs to go Quote Link to comment https://www.bigmacktrucks.com/topic/74492-r-model-electrical-help/#findComment-557671 Share on other sites More sharing options...
Joey Mack Posted August 27 Share Posted August 27 Have you looked at the 2 terminal strips on the firewall by the steering shaft? Quote Link to comment https://www.bigmacktrucks.com/topic/74492-r-model-electrical-help/#findComment-557679 Share on other sites More sharing options...
JoeH Posted August 27 Share Posted August 27 $7 through your local Mack Dealer, shop manual # 8-501. 1 Quote Link to comment https://www.bigmacktrucks.com/topic/74492-r-model-electrical-help/#findComment-557685 Share on other sites More sharing options...
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