Sparky Needed.... Alternator Question URGENT [Archive]

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VZSSTT17-02-2010, 04:33 PMSo my alternator is overcharging on my vz ss LS1, I was going to put a spare on which is off a VY SS LS1 But i noticed the plug is different. The Vz LS1 Alternator has wires L and FR (Light and Field Return) While the VY Alternator has L And S (Light and Sense) Question is can i fit the vy alternator by putting the sense to bat pos wiring the warning light in and leaving off the field return wire. If so what effect can leaving field return off if any (and no the engine warning light does not come on as i have started the car with the plug off already) As a temp solution until other one is fixed?? ADVICE NEEDED!! Cheers All clubbie17-02-2010, 05:23 PMMate, having just changed an alternator that borked itself and fritzed the cable that goes back to the positive on the battery I can tell you 100% that the alternators are different. The VY has it's own regulator the VZ one is controlled by the PCM. Original VZ alternators are considerable cheaper than the VY one's. VZSSTT17-02-2010, 11:11 PMMate, having just changed an alternator that borked itself and fritzed the cable that goes back to the positive on the battery I can tell you 100% that the alternators are different. The VY has it's own regulator the VZ one is controlled by the PCM. Original VZ alternators are considerable cheaper than the VY one's. Thanks for the info. I decided what the hell i will have a go anyways... After some time and swearing (Thanks to The TT Kit installed) I got old one out. what is worth noting is both alternators are identical bar the plug. And even tho you say the PCM Regulates the alternator still has a reg in the back. Anyways i fitted the VY alt in place and wired it as i previously stated. Started the Car no smoke but NO charge??? Now Theoretically with the B+ S and L wires connected correctly it should charge.. After Probing a test light around i descovered that the L Wire coming from the Harness side was not throwing down a signal to Excite Diodes. So i put B+ to one side of my test light and touched the L Wire and what do ya no PERFECT charging...... Now comes question time.... Does the FR wire on the orignal alt have to throw a signal back before a signal gets thrown down the L Wire? IF anyone knows how the field return works please jump on in and let us no..... I still question that the PCM Regulates on a 5.7L LS1? the original alternator doesnt have a clutch either like a 6L and it definetly appears to have a reg in back. I drove it for about 50Kms after manually exciting and everything went Spot on. Car maintained a stable voltage Did not miss at all V to sensors were stable. Fuel Eco was spot on. Should i just manually wire a ign and Light to excite and be done with it. Or does the new Alt have ANY benefits?? btw no check codes engine lights on after manually exciting either.... ANYONE???? Desertws617-02-2010, 11:29 PMWouldn't it be best to just get the proper part in the first place? It might work ok the way you have it connected now, but what happens later? Are you willing to risk doing major damage to your car, and there are plenty of expensive parts in there. Computers Wiring harness Battery Cables Stereo system A new proper alternator seems cheap by comparison. The alternators might look identical but do they have the exact same amperage rating? Just my 2c worth mate. ,Steve VZSSTT18-02-2010, 12:00 AMWouldn't it be best to just get the proper part in the first place? It might work ok the way you have it connected now, but what happens later? Are you willing to risk doing major damage to your car, and there are plenty of expensive parts in there. Computers Wiring harness Battery Cables Stereo system A new proper alternator seems cheap by comparison. The alternators might look identical but do they have the exact same amperage rating? Just my 2c worth mate. ,Steve Thanks for the opinion.. Yea they have the exact same amperage rating. And provided that one is internally regulated and cannot overcharge i cant see it could damage anything. I will endevour to fix the original problem i just hope if it is controlled via the PCM it is not in the PCM as it could be a rather expensive exersize. I am mainly chasing some Info on why the change between VY LS1s and VZ LS1s? My bet is would be to stabilze any fluctuation in battery voltage, if thats the case i think its an overkill Just chasing some logical reasoning. and for what it is worth i am an auto electrician by trade, hense would not hook things up directly and damage them. Just trying to get some advice on something i have not came across in the past.... HSV Listy06-12-2010, 02:04 PMHad this overcharging happen to me last week. I was on the circuit too. I noticed the engine warning light come on so I checked with the OBD LM2 connection with the engine on idle and no faults came up. I reset it and all good and light went out. I went for some more laps and once again the engine warning came on. No biggie I thought as a loose wire or moisture so I kept going. Eventually the engine started to sputter, all the gauges went to nothing and the engine went into some sort limp mode where it would just idle but still just run. I would say the regular was on its way out with the engine warning light on then eventually let go and sent into full over charge (like 30 odd volts) If I revved the engine while checking the LM2 earlier for fault codes I may of come up as a warning but impossible to prove now though. So a note for others if you engine warning light comes up and there is no faults just check the charging volts as a just in case. Also if you dash goes to nothing and car starts to run like crap just check the charging volts (around 14.2 is should be). The alternator light seems to be only on low volts and did not come on with high volts. I thought that would be a forgone thing to put a big warning light on a car considering the damage it may have cased. (there was a warning light but it did not tell me what) It did reset everything, including engine and dash when I disconnected the battery for 5 minutes and put it back on and as long as I putted to the repair shop below 800rpm it was fine. Fortunately the GTS can put around no problems between 600 and 800 rpm. Another point it is dam near impossible to do a road side disconnect of the alternator to keep going when the engine is stinking hot too. Pain to get to depending what else is in the way. peter b07-12-2010, 08:11 AMThanks for the opinion.. Yea they have the exact same amperage rating. And provided that one is internally regulated and cannot overcharge i cant see it could damage anything. I will endevour to fix the original problem i just hope if it is controlled via the PCM it is not in the PCM as it could be a rather expensive exersize. I am mainly chasing some Info on why the change between VY LS1s and VZ LS1s? My bet is would be to stabilze any fluctuation in battery voltage, if thats the case i think its an overkill Just chasing some logical reasoning. and for what it is worth i am an auto electrician by trade, hense would not hook things up directly and damage them. Just trying to get some advice on something i have not came across in the past.... From memory from when I worked at holden these alternators are not interchangable. Wouldn't it be easier to reco the original alternator. It would be nice if it were interchangable and for the life of me I cant remember what else was different apart from what is already stated. But definately won't work im afraid VX2VESS07-12-2010, 09:37 AMhttp://holmart.com.au/online/prod2025.htm http://holmart.com.au/online/images/102_5521.jpg http://holmart.com.au/online/category4_1.htm Powered by vBulletin® Version 4.2.5 Copyright © 2025 vBulletin Solutions Inc. All rights reserved.