Home  |  Forums  |  914 Info  |  Blogs
914World.com - The fastest growing online 914 community!
Porsche, and the Porsche crest are registered trademarks of Dr. Ing. h.c. F. Porsche AG. This site is not affiliated with Porsche in any way.
Its only purpose is to provide an online forum for car enthusiasts. All other trademarks are property of their respective owners.

Welcome Guest ( Log In | Register )

> Alternator question., Not Charging.
Olympic 914
post Mar 25 2018, 05:05 PM
Post #1

I hate body work

Group: Members
Posts: 803
Joined: 7-July 11
From: Pittsburgh PA
Member No.: 13,287
Region Association: None

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.
Leave the VR in place and short between those pins?
User is offlineProfile CardPM
Go to the top of the page
+Quote Post

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
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
euro911   Jerry, what's the best method for bench testin...   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

Reply to this topicStart new topic
1 User(s) are reading this topic (1 Guests and 0 Anonymous Users)
0 Members:


- Lo-Fi Version Time is now: 20th October 2018 - 12:22 PM