Alternator sensing Wire Mod- Need more Volts
#1
Senior Member
Thread Starter
![Default](https://www.gmforum.com/images/icons/icon1.gif)
Similar to a mother boards that suffers from voltage droop... that is what I am again experiencing in the Park Ave.
I was manually charging the Odyssey battery yesterday for a reason....
With a basic load on, fan on lights on & brakes lights on at idle, volts drops from interior accessory socket reading to 12.2 -12.4 volts..that is huh?? Should it not be kicking out at least 13.6 volts?.
This is always after driving when it gets hot outside.. doesn't help either..
At 1800 rpm with same load, I am lucky to see 13.4 volts....this is not charging the battery very well. This was happening with the other stock alternator before I ordered the high output & it is doing the same thing again with the new ALT. With the c-tek manual charger it was putting out 14.64V
Most cars can & should put out/charge easily at 13.9+ at highway speeds. I will get the ALT loads & Diodes Tested again by the snap on machine soon...maybe something up with PCM module?
Ok onto my next question for you electronic tech savvy folks...CS-130D alt..160 amp..
For those that know the laws..could it be the greater the amperage output the lesser voltage rule going on here?
There is a 4 wire connector one of which should be the exciter wire, which as far as I know is what tells the alt to get with it and put some volts out...
From what I understand installing a diode (not sure which one) into the exciter wire, u can fool the ALT into seeing a lower voltage than is present, and hopefully then the ALT kicks out another 1/2 volt or so...anything would be better than what I got...
Thanks for some info & help I need some more volts please!
I found Dan'* tech write up I am not sure that applies to my 97 4 pin system though?
https://www.gmforum.com/electrical-1...rnator-278806/
Note to eliminate confusion I decided to create a new Thread for this issue.
I was manually charging the Odyssey battery yesterday for a reason....
With a basic load on, fan on lights on & brakes lights on at idle, volts drops from interior accessory socket reading to 12.2 -12.4 volts..that is huh?? Should it not be kicking out at least 13.6 volts?.
This is always after driving when it gets hot outside.. doesn't help either..
At 1800 rpm with same load, I am lucky to see 13.4 volts....this is not charging the battery very well. This was happening with the other stock alternator before I ordered the high output & it is doing the same thing again with the new ALT. With the c-tek manual charger it was putting out 14.64V
Most cars can & should put out/charge easily at 13.9+ at highway speeds. I will get the ALT loads & Diodes Tested again by the snap on machine soon...maybe something up with PCM module?
Ok onto my next question for you electronic tech savvy folks...CS-130D alt..160 amp..
For those that know the laws..could it be the greater the amperage output the lesser voltage rule going on here?
There is a 4 wire connector one of which should be the exciter wire, which as far as I know is what tells the alt to get with it and put some volts out...
From what I understand installing a diode (not sure which one) into the exciter wire, u can fool the ALT into seeing a lower voltage than is present, and hopefully then the ALT kicks out another 1/2 volt or so...anything would be better than what I got...
Thanks for some info & help I need some more volts please!
I found Dan'* tech write up I am not sure that applies to my 97 4 pin system though?
https://www.gmforum.com/electrical-1...rnator-278806/
Note to eliminate confusion I decided to create a new Thread for this issue.
__________________
1997 Buick Pk Ave (Soft Ride) Suspension!
1997 Buick Pk Ave (Soft Ride) Suspension!
![Smile](https://www.gmforum.com/gm/images/smilies/smile.gif)
Last edited by Soft Ride; 05-30-2014 at 04:28 AM.
#2
Senior Member
Posts like a 4 Banger
![Default](https://www.gmforum.com/images/icons/icon1.gif)
I haven't dug into this yet and being new to the Bonnie, I'm curious to find out also. We had a wire mod on the GPs because the alternator wire size from the factory was actually too small to handle any real loads like the amps, electric intercooler pumps, heavier light systems, etc. without such a power drop as yours. ZZP sold a wiring kit a lot of folks used to boost voltage but I opted for the 160A alternator from Motor City Reman and made my own mod for the charging system. Since the battery is in the back of mine instead of under the hood, it may well not work on the Bonnie but I'm thinking of doing some checking soon. ON the '97 GP, I ran a dual post battery with top and side posts. The side posts were used for the regular factory battery cables & I ran two universal battery cables from the top posts with the positive hooked directly to the alternator with the factory wire left in place and the negative was grounded to the alternator mount bolt. No more dim lights when the subs hit with the air and headlights (retro fitted BMW projectors) on and was kicking. Most of the time the volt gauge read at or slightly above 14V and life was good.
Maybe someone can also answer if this type wiring issue exists with yours or the Bonnevilles since I haven't put the meter on mine to see what it puts out yet. Soooo many projects and things to do to it and haven't got there yet or even asked the question before but my amps and Kenwood head unit are dying to get installed and the two amps SUCK power!
Maybe someone can also answer if this type wiring issue exists with yours or the Bonnevilles since I haven't put the meter on mine to see what it puts out yet. Soooo many projects and things to do to it and haven't got there yet or even asked the question before but my amps and Kenwood head unit are dying to get installed and the two amps SUCK power!
#3
Senior Member
Thread Starter
![Default](https://www.gmforum.com/images/icons/icon1.gif)
Since I dont work in the shop, one thing is certain I believe, that if the PCM controls this situation there must be a way to read some sort of live data to see what it is doing.
I am just not familiar enough and am not a certified tech.
I also believe I will use my buds scanner and see if there are any PCM trouble codes just for starters.
I did rewire a bit for my my High Output Alt Requirement/Rewire/Install.
https://www.gmforum.com/buick-172/al...please-305375/
I am just not familiar enough and am not a certified tech.
I also believe I will use my buds scanner and see if there are any PCM trouble codes just for starters.
I did rewire a bit for my my High Output Alt Requirement/Rewire/Install.
https://www.gmforum.com/buick-172/al...please-305375/
__________________
1997 Buick Pk Ave (Soft Ride) Suspension!
1997 Buick Pk Ave (Soft Ride) Suspension!
![Smile](https://www.gmforum.com/gm/images/smilies/smile.gif)
Last edited by Soft Ride; 05-30-2014 at 05:17 AM. Reason: add link
The following users liked this post:
damadtech (05-30-2014)
#4
Retired
![](https://www.gmforum.com/images/ranks/veteran_army.png)
![Default](https://www.gmforum.com/images/icons/icon1.gif)
How old is the battery?
__________________
Retired Administrator
Retired Administrator
#5
Senior Member
True Car Nut
![Default](https://www.gmforum.com/images/icons/icon1.gif)
the older hbodies dont have sense wires for proper reacting to the load, so the common fix is if you want to see the voltage in the car you run a sense wire in the car. all gm wires are undersized that adds to the issues but if you connect the wire to somewhere in the interior fuse panel, that should create more volts when needed throughout the system
#6
Senior Member
Posts like a 4 Banger
![Default](https://www.gmforum.com/images/icons/icon1.gif)
I did rewire a bit for my my High Output Alt Requirement/Rewire/Install.
https://www.gmforum.com/buick-172/al...please-305375/
https://www.gmforum.com/buick-172/al...please-305375/
#7
Senior Member
![](/images/badges/ASECertified.png)
![Default](https://www.gmforum.com/images/icons/icon1.gif)
"With a basic load on, fan on lights on & brakes lights on at idle, volts drops from interior accessory socket reading to 12.2 -12.4 volts..that is huh?? Should it not be kicking out at least 13.6 volts?.
This is always after driving when it gets hot outside.. doesn't help either..
At 1800 rpm with same load, I am lucky to see 13.4 volts....this is not charging the battery very well. "
If you go out to any stock GM car, those readings will be normal......at warm idle, and under a load, you will not get 12.6 volts.....No way will your alternator be charging at 13.6, at warm idle under a load.....
At 2000 rpms, with a warm engine, with a load, 13.4 volts sounds about right.....
As Mike asked, if you have an old battery/bad connection, that can skew the voltages a little lower.....
I don't know if anyone can print the TSB that pertains to this....the TSB has a graph of the output of the alternator for a cold and warm engine, and how voltage will drop, if the alternator is warm, and especially under a load, like for example, at night, when you come to a stop and the lights may dim a little....
This is always after driving when it gets hot outside.. doesn't help either..
At 1800 rpm with same load, I am lucky to see 13.4 volts....this is not charging the battery very well. "
If you go out to any stock GM car, those readings will be normal......at warm idle, and under a load, you will not get 12.6 volts.....No way will your alternator be charging at 13.6, at warm idle under a load.....
At 2000 rpms, with a warm engine, with a load, 13.4 volts sounds about right.....
As Mike asked, if you have an old battery/bad connection, that can skew the voltages a little lower.....
I don't know if anyone can print the TSB that pertains to this....the TSB has a graph of the output of the alternator for a cold and warm engine, and how voltage will drop, if the alternator is warm, and especially under a load, like for example, at night, when you come to a stop and the lights may dim a little....
#8
Senior Member
Thread Starter
![Default](https://www.gmforum.com/images/icons/icon1.gif)
Mike that battery is currently 25 months old.
Last Midtronics load test (9 months ago) tested good at 880 CCA.
(without manual charging first)
I am going to get another test done soon.
![](https://www.gmforum.com/attachments/buick-172/12104-alternator-sensing-wire-mod-need-more-volts-odysseybatterynewapr2012_zps8468561f.jpg?dateline=1401469547)
In reality the car starts fine and I have upgraded the system the best I can.
I know that the Odyssey would appreciate a higher charging voltage though.
I need to manually charge more often if I want batteries to last in this car.
Last Midtronics load test (9 months ago) tested good at 880 CCA.
(without manual charging first)
I am going to get another test done soon.
![](https://www.gmforum.com/attachments/buick-172/12104-alternator-sensing-wire-mod-need-more-volts-odysseybatterynewapr2012_zps8468561f.jpg?dateline=1401469547)
In reality the car starts fine and I have upgraded the system the best I can.
I know that the Odyssey would appreciate a higher charging voltage though.
I need to manually charge more often if I want batteries to last in this car.
__________________
1997 Buick Pk Ave (Soft Ride) Suspension!
1997 Buick Pk Ave (Soft Ride) Suspension!
![Smile](https://www.gmforum.com/gm/images/smilies/smile.gif)
#9
Senior Member
Thread Starter
![Default](https://www.gmforum.com/images/icons/icon1.gif)
the older hbodies dont have sense wires for proper reacting to the load, so the common fix is if you want to see the voltage in the car you run a sense wire in the car. all gm wires are undersized that adds to the issues but if you connect the wire to somewhere in the interior fuse panel, that should create more volts when needed throughout the system
![thumbup](https://www.gmforum.com/gm/images/smilies/28.gif)
__________________
1997 Buick Pk Ave (Soft Ride) Suspension!
1997 Buick Pk Ave (Soft Ride) Suspension!
![Smile](https://www.gmforum.com/gm/images/smilies/smile.gif)
#10
Senior Member
True Car Nut
![Default](https://www.gmforum.com/images/icons/icon1.gif)
i keep forgetting the pa is its own animal and none of my sources have the stock wiring, but you need to run wire "*" inside the car on a cs130, on some cars its just jumpered to 12v or jumped to the alt post
![](https://www.gmforum.com/attachments/buick-172/12105-alternator-sensing-wire-mod-need-more-volts-cs130dplug.jpg?dateline=1401475590)