 Alternator question., Not Charging. |
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| Olympic 914 |
 Mar 25 2018, 05:05 PM
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#1
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 Group: Members Posts: 1,710 Joined: 7-July 11 From: Pittsburgh PA Member No.: 13,287 Region Association: North East States 
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Took the car out for a drive today, planning on going to dinner. everything is working as it should. getting on the PA turnpike and I had to accelerate briskly to get into traffic, and a moment later I noticed that the RED alternator light had come on. Pulled of at a wide spot to check the belt and wires and shut it off. Not checking the belt with it running. Belt good, plug tight, tapped the VR a couple times for good measure and started it back up. Light still on and now my Autometer AFR gauge just had bars. I know that is because it doesn't turn on until the voltage is +13v So not charging.
Now I am on a limited access highway with the next exit `12-15 miles away. Good thing had the battery fully charged on the tender before I left the house. So I made it to the next exit, turned around and headed back home for a total of 35 miles on battery only. Whew. But that shot dinner..... Replace the VR with another I had that previously tested good. still no charging. checked the plug on the relay plate again. looks good. I have not yet checked the wire connections at the alternator, possibly a wire vibrated loose during the brisk acceleration. Now the question I read to test the VR to short between D+ and DF and if the alternator is good voltage at the battery will go to alternator maximum of about 15-16V So do I REMOVE the VR for this test? and jump between the D+ and DF at the relay plate. OR Leave the VR in place and short between those pins? |
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| Gatornapper |
Sep 4 2019, 06:21 AM
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#2
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Senior Member Group: Members Posts: 1,263 Joined: 22-September 17 From: Woods west of Richmond, VA Member No.: 21,449 Region Association: South East States
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Re: VR not working.
Both VR's I have get very hot - too hot to touch. So it seems that they are trying to work - lot of activity going on electrically to produce all that heat...... |
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| Spoke |
Sep 4 2019, 07:06 PM
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#3
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Jerry Group: Members Posts: 7,107 Joined: 29-October 04 From: Allentown, PA Member No.: 3,031 Region Association: None
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QUOTE(Gatornapper @ Sep 4 2019, 08:21 AM)  Re: VR not working. Both VR's I have get very hot - too hot to touch. So it seems that they are trying to work - lot of activity going on electrically to produce all that heat...... Just to check: both VR's get very hot but both do not work and no charging is going on, correct? No charging means you see less than 12.6V while running. It is odd that 2 VR's both do the same thing (get hot) but don't work. However when you short DF to D+ you get full charging from the alternator. One more thing to check with engine off, check: remove the VR and disconnect the alternator cable. Then check resistance between D+ to DF, D+ to D- and D+ to D-. Just make sure there are no shorts on the relay board. All should be infinite. Also measure resistance D+ to chassis; DF to chassis; and D- to chassis. All should be infinite although D+ might show some resistance as D+ is connected to the GEN bulb and to stuff on the other side of the bulb. Again looking for shorts to ground. Just want to make sure there are no shorts on the relay board. |
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Posts in this topic
Olympic 914 Alternator question. Mar 25 2018, 05:05 PM
Spoke
Took the car out for a drive today, planning on g... Mar 26 2018, 07:21 AM
Olympic 914
Yes, disconnect only the VR. Jump the D+ and DF... Mar 26 2018, 08:37 AM falcor75 Ground cable between gearbox and chassi? Mar 26 2018, 08:47 AM Olympic 914
Ground cable between gearbox and chassi?
New, C... Mar 26 2018, 08:55 AM Mikey914 Well if all works well great. I'd try driving ... Mar 26 2018, 09:40 AM Olympic 914
Well if all works well great. I'd try driving... Mar 26 2018, 09:50 AM Olympic 914 So this alternator problem continues to vex me. ... Apr 18 2018, 07:20 PM malcolm2
Next step will be to pull the alternator and pro... Apr 19 2018, 08:04 AM McMark Dying relay board? Apr 19 2018, 05:30 AM Olympic 914
Dying relay board?
I did hook up another relay ... Apr 19 2018, 06:20 AM malcolm2 I have had some ALT probs too. Spoke must keep th... Apr 19 2018, 07:08 AM McMark I think malcolm2 is right -- and I don't think... Apr 19 2018, 07:34 AM Tdskip
I think malcolm2 is right -- and I don't thin... Mar 28 2019, 06:13 AM malcolm2 I am bored today. Hey Spoke, how is this???
Apr 19 2018, 09:13 AM Olympic 914 There is also this.
I performed the tests belo... Apr 19 2018, 11:55 AM McMark Damn!!! That’s a fantastic post. :dr... Apr 19 2018, 04:09 PM bulitt Yes, you must excite the Alternator to wake it up.... Apr 19 2018, 04:58 PM Mikey914
Yes, you must excite the Alternator to wake it up... Apr 20 2018, 10:20 AM Edward Blume I had my stock Bosch alternator professionally reb... Apr 19 2018, 05:58 PM jcd914 I don't recall the years but there was a TSB f... Apr 20 2018, 10:36 AM Olympic 914 On Thursday took the alternator to the local FLAPS... Apr 22 2018, 11:52 AM Spoke :beer2: Apr 22 2018, 12:07 PM GregAmy That post #15 is a gem...
Camping onto this one f... May 13 2018, 01:22 PM Spoke
Does everyone else's GEN light come on with k... May 13 2018, 02:20 PM GregAmy Yes, the light is on with key on and engine not ru... May 13 2018, 03:45 PM Spoke
Yes, the light is on with key on and engine not r... May 13 2018, 05:30 PM GregAmy
= About the measurements, here's what I think... May 14 2018, 05:05 AM GregAmy
= About the measurements, here's what I think... May 14 2018, 03:55 PM GregAmy
Camping onto this one for a slightly different pr... Mar 25 2019, 07:58 PM worn
Camping onto this one for a slightly different p... Mar 25 2019, 08:13 PM GregAmy
Maximum alternator output is triggered when you b... Mar 26 2019, 05:06 AM DRPHIL914
Camping onto this one for a slightly different p... Mar 27 2019, 10:33 AM VaccaRabite
Greg,
Glad you solved it. My issue was the lacke... Mar 27 2019, 07:39 PM euro911 I have several 'unknown condition' units I... May 14 2018, 02:27 AM GregAmy Aaaaand a new voltage regulator...
...didn't ... May 14 2018, 04:32 PM Spoke Bummer. I didn't think the VR was at fault but... May 15 2018, 07:04 PM GregAmy Yep. All grounds and battery cables replaced by me... May 16 2018, 06:42 AM dangrouche
Yep. All grounds and battery cables replaced by m... May 17 2018, 11:27 AM GregAmy the pigtail at the alternator end needs the altern... May 18 2018, 08:07 AM dangrouche https://www.aspwholesale.com/index.php
here is a ... May 18 2018, 11:24 AM Gatornapper Ok, friends - this thread has been very helpful, b... Aug 31 2019, 07:07 PM Spoke Try these measurements with engine running; lights... Aug 31 2019, 08:14 PM Gatornapper Only work on car had nothing to do with electrical... Sep 1 2019, 07:20 AM Spoke
Should I read these voltages at the VR pins as we... Sep 1 2019, 07:48 AM Gatornapper I have quite a bit of experience with circuit boar... Sep 1 2019, 11:36 AM Gatornapper Spoke -
Ran tests tonight after 1 hour drive, so ... Sep 3 2019, 06:26 PM Spoke
Spoke -
Ran tests tonight after 1 hour drive, so... Sep 3 2019, 07:34 PM Gatornapper Spoke - yes, GEN light is OFF until I turn on head... Sep 3 2019, 08:08 PM 914Sixer Do you have a spare relay board to swap out? Sep 1 2019, 07:41 AM 904svo Just a WAG, measure the voltage between the altern... Sep 3 2019, 07:28 PM Gatornapper Thanks for the idea - I'll do that. But previ... Sep 3 2019, 07:37 PM Olympic 914
Re: VR not working.
Both VR's I have get ve... Sep 4 2019, 06:45 AM Gatornapper Thanks - would like to get one....
Checked BERU... Sep 4 2019, 09:42 AM euro911 Typically can't purchase products from compani... Sep 4 2019, 11:43 AM Gatornapper Thanks Mark.
Typically can't purchase produc... Sep 4 2019, 05:21 PM Gatornapper Ok, test results:
Relay board not the problem....... Sep 4 2019, 05:28 PM Spoke
Ok, test results:
Relay board not the problem...... Sep 4 2019, 07:24 PM VaccaRabite
Keep in mind that without the alternator working,... Sep 5 2019, 07:58 AM Gatornapper Zach -
First running one to the shroud. Then ch... Sep 5 2019, 11:03 AM jcd914 Maybe I missed in the thread but did you check vol... Sep 4 2019, 05:53 PM Gatornapper Jim - will check tomorrow, but checked all other p... Sep 4 2019, 08:09 PM Gatornapper Spoke -
Will run all suggested tests tomorrow - ... Sep 4 2019, 08:23 PM Spoke
So when I check D- to chassis that's with the... Sep 5 2019, 04:15 AM Gatornapper Dumb question: if the VR is in place, where do I ... Sep 5 2019, 10:59 AM Spoke
Dumb question: if the VR is in place, where do I... Sep 5 2019, 03:58 PM Spoke This diagram shows which signals are which.
In th... Sep 5 2019, 04:02 PM Gatornapper I should have told you all I don't have regula... Sep 5 2019, 04:54 PM Spoke It makes me wonder if the VR is not starting becau... Sep 5 2019, 05:41 PM Gatornapper Ok, I can do that, but then I need someone else at... Sep 5 2019, 06:12 PM Gatornapper I have another idea: I'll bring a 1 amp fused... Sep 5 2019, 06:18 PM Spoke
I have another idea: I'll bring a 1 amp fuse... Sep 5 2019, 06:41 PM Gatornapper Spoke -
Ok, let's assume that jumping 12+ to ... Sep 5 2019, 07:05 PM Spoke
Spoke -
Ok, let's assume that jumping 12+ to... Sep 5 2019, 07:29 PM Spoke
I have another idea: I'll bring a 1 amp fuse... Sep 6 2019, 04:47 PM Gatornapper
I have another idea: I'll bring a 1 amp fus... Sep 7 2019, 05:46 AM Gatornapper Spoke -
D- to engine or chassis with engine runni... Sep 5 2019, 06:05 PM 914Sixer Adding information from owners manual. Please rea... Sep 6 2019, 02:54 PM Gatornapper Mark - yes, I know this - so I have 3 bad VR's... Sep 6 2019, 03:34 PM 914Sixer I would say the Bosch ones are ok. Is the alterna... Sep 6 2019, 03:54 PM Gatornapper I would say yes.
But remember, it puts out full v... Sep 7 2019, 05:32 AM Gatornapper Post I just made on Pelican's forum:
Greg -
... Sep 7 2019, 07:15 PM ClayPerrine You can't use just any light for the alternato... Sep 7 2019, 07:20 PM Gatornapper Clay -
The 2nd VR I tried is NOS I got from a rel... Sep 7 2019, 07:53 PM Gatornapper Clay -
The [b]strong implication of this statemen... Sep 8 2019, 05:54 AM Spoke Did you do the test with the 1156 bulb across the ... Sep 8 2019, 09:41 AM Gatornapper Yes. Nothing happened. Did not energize the arma... Sep 8 2019, 11:24 AM Spoke
Yes. Nothing happened. Did not energize the arm... Sep 8 2019, 04:45 PM Gatornapper
[quote name='Gatornapper' post='2745248' date='Se... Sep 8 2019, 06:17 PM euro911 At this point I'm suspecting one of the altern... Sep 8 2019, 07:25 PM Gatornapper Mark -
Totally understand - but if one of the di... Sep 8 2019, 07:33 PM Spoke
At this point I'm suspecting one of the alter... Sep 8 2019, 08:58 PM VaccaRabite
At this point I'm suspecting one of the alte... Sep 9 2019, 11:06 AM Gatornapper Memories guys? Jerry & Zack - Long ago I jump... Sep 9 2019, 07:26 PM Spoke
...I jumped D+ & DF and did get full 17v at t... Sep 9 2019, 10:50 PM Gatornapper Ok, will do today.
One additional bit of info: G... Sep 10 2019, 07:21 AM Spoke Here's a way to do a quick test on the VR. I j... Sep 9 2019, 11:52 PM Spoke Part 2 of the VR test is to check the D+ and DF vo... Sep 10 2019, 12:04 AM |
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