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my alternator is getting 13.8v


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still_walkin 
Silver - Posts: 644
Silver spacespace
Joined: April 18, 2007
Location: California, United States
Posted: February 10, 2010 at 4:45 PM / IP Logged  
So check the battery band the alt is ok
1993 sdv
Alpine 4x6 6x9 5 1/4 swr-10d4
alpine v60
12.5 VGA flip down
Nettop pc w/10" touch screen
78nova
5-re audio 5x7 ,10" sub &
Xtx-500.5
"Take the faceplate off get the jumperpack"
still_walkin 
Silver - Posts: 644
Silver spacespace
Joined: April 18, 2007
Location: California, United States
Posted: February 11, 2010 at 5:50 PM / IP Logged  
So here's the update I let the car sit 11hours and the voltage with the viper alarm on was 12.40 so I'm thinking the battery is good .
1993 sdv
Alpine 4x6 6x9 5 1/4 swr-10d4
alpine v60
12.5 VGA flip down
Nettop pc w/10" touch screen
78nova
5-re audio 5x7 ,10" sub &
Xtx-500.5
"Take the faceplate off get the jumperpack"
oldspark 
Gold - Posts: 4,913
Gold spacespace
Joined: November 03, 2008
Location: Australia
Posted: February 11, 2010 at 10:57 PM / IP Logged  
Excellent!
The battery is low, but doesn't seem collapsed. (95% confidence?)
Low is expected anyhow since it is undercharging.... (99% "not the battery" confidence.)
So it's an alternator problem - unless connection problem.... (fuse-links etc)
You mentioned no charge lamp.
If it's a single-wire alternator, can you disconnect the D+ wire (at the alternator) and run a lamp from D+ to +12V (battery) to see if it lights? Ignition can be off. The bulb should be (12V) 2W or 3W, else 5W, or maybe 10W - but no larger.
If it lights, can you keep it connected, start the engine and see if it extinguishes.
Please do not allow hands or ties or clothing to be caught in any moving part, fan belt, fan blade, alternator fan or pulley etc - it can hurt a lot, and kill a lot too!
If it does extinguish, check voltages at the alternator output (aka B or B+, should be 13.6 - 14.4V depending on RPM), and at the battery +12V (which should be close or the same as the alt's B+). Heed my former plea - ie WARNING!
If the alt B+ varies from the battery+, you have a bad connection or blown fuse between B+ and Batt+ (aka B+).
If the D+ lamp doesn't initially glow/light, the regulator is faulty. It it doesn't extinguish after starting, the alternator or regulator is faulty or you have a broken fan belt, or missing pulleys etc. Or started the wrong engine.
If it isn't above 13.6 with RPM and loads (eg, headlights), the if not a slipping fan belt, the alt/reg is faulty. (Worn brushes, blown power diodes, etc.)
If it's a 2 or 3 wire alternator (regulator), the same testing applies, but you need to connect the 2W-3W test light to the D+ which they usually label as "L" (charge Lamp) as opposed to S for Sense or IGN, and I for IGN.
The L circuit should handle the extra "not big" test lamp for battery+ - ie, a 12V 2W or 3W bulb.
Note - although LEDs will illuminate like a bulb, they may not pass sufficient tickle current, and it can be hard to tell if they extinguished...
[FYI.... Because most alternator D+ or L outputs are say 1.2V under the +12V supply which is enough to light a LED as well as cause the charge lamp and various tested dash bulbs to glow dimly (at night) - and hence why modern cars often switch a relay to switch or power the tested dash lights instead. ]     
--- OR ----
Did other lamps normally come on with ignition but engine NOT started - which then extinguished with the charge lamp? This does not include oil-pressure lamps (nor handbrake & hi-beam etc), but things like "brake-fault" of low fuel (for EFI) lamps that are tested upon IGN-on.
And do they still come on?
Of they do, it suggests a blown charge lamp (rather than a faulty alternator).
Many (most?) alternators must have a charge lamp to ensure that they begin to charge. Without it, they may charge, but often not - especially after a few hours since last charging.
Once initiated, the alternator may not need the charge lamp. (It depends on the model etc.)
And for older cars that had "tested bulbs" when the system was not charging, the tested bulbs could also provide the trickle or tickle current provided via the charge lamp to initiate charging.
But later cars use relays or other circuits for such tested bulbs and will not initiate charging. (IE - they are not connected via diodes to the charge lamp circuit from the alternator/regulator.)
There you go.
Short and sweet.
still_walkin 
Silver - Posts: 644
Silver spacespace
Joined: April 18, 2007
Location: California, United States
Posted: February 11, 2010 at 11:03 PM / IP Logged  
Thans ill look into that. The no charge light came on with the other lights but when it stalled it was the only light on after it cut off my voltage has been the same so I'm think the alt needs to be rebuilt. I also have the big3 installd as well.
1993 sdv
Alpine 4x6 6x9 5 1/4 swr-10d4
alpine v60
12.5 VGA flip down
Nettop pc w/10" touch screen
78nova
5-re audio 5x7 ,10" sub &
Xtx-500.5
"Take the faceplate off get the jumperpack"
oldspark 
Gold - Posts: 4,913
Gold spacespace
Joined: November 03, 2008
Location: Australia
Posted: February 12, 2010 at 10:43 PM / IP Logged  
As I understand it, upon ignition switch on, the charge lamp is on along with the other "tested" lamps.
The engine starts and all extinguish.
Upon stalling, only the charge light comes on. (And later the oil light etc - but that is not a tested light and is thus irrelevant.)
That sounds like the alternator & regulator is charging & working but only partially. Maybe worn brushes or some other fault is causing the undercharging.
Of course we did check fan belt tension, twiddled or cleans the battery connections, and checked grounds etc didn't we? my alternator is getting 13.8v - Page 2 -- posted image.
And for loose/bad fuse(s) between alt & battery... (Remove & refit/reconnect etc to re-make bad connections.)     
FYI - On earlier vehicles with diode-connected to charge-lamp bulb testing, upon engine stall or loss if charging, all the bulbs involved would light up. (Scary at night - engine stalls and several angry red & amber lamps hit you. Though it made charge lamp circuit faults easy to pinpoint because it was an "all for one" light up situation.)
Later vehicles adopted indirect bulb testing and hence could prevent other lamps lighting upon charge faults (including engine stall). IE - the charge lamp circuit after ignition-on would cause lamp testing via a relay or ECU etc, but once started, that testing link would be severed. Hence an engine stall or alternator failure would only light the charge lamp instead of causing panic & abandon ship screams.
still_walkin 
Silver - Posts: 644
Silver spacespace
Joined: April 18, 2007
Location: California, United States
Posted: February 12, 2010 at 10:55 PM / IP Logged  
thanks ill check for loose wires
1993 sdv
Alpine 4x6 6x9 5 1/4 swr-10d4
alpine v60
12.5 VGA flip down
Nettop pc w/10" touch screen
78nova
5-re audio 5x7 ,10" sub &
Xtx-500.5
"Take the faceplate off get the jumperpack"
still_walkin 
Silver - Posts: 644
Silver spacespace
Joined: April 18, 2007
Location: California, United States
Posted: February 26, 2010 at 7:20 AM / IP Logged  
Ok guys I was trying to park it and it stalled the no charge and oil light came on but my head lights were bright so I turned it off restart the car and it came on right away checked the voltage its running 13.5. Turn the radio and hi beams on it hits 14 wht gives
1993 sdv
Alpine 4x6 6x9 5 1/4 swr-10d4
alpine v60
12.5 VGA flip down
Nettop pc w/10" touch screen
78nova
5-re audio 5x7 ,10" sub &
Xtx-500.5
"Take the faceplate off get the jumperpack"
oldspark 
Gold - Posts: 4,913
Gold spacespace
Joined: November 03, 2008
Location: Australia
Posted: February 26, 2010 at 7:56 AM / IP Logged  
You stalled it. The rest is typical.
Voltages vary depending on the loads and how things are wired.
still_walkin 
Silver - Posts: 644
Silver spacespace
Joined: April 18, 2007
Location: California, United States
Posted: February 26, 2010 at 8:12 AM / IP Logged  
Its a factory except for the big 3
1993 sdv
Alpine 4x6 6x9 5 1/4 swr-10d4
alpine v60
12.5 VGA flip down
Nettop pc w/10" touch screen
78nova
5-re audio 5x7 ,10" sub &
Xtx-500.5
"Take the faceplate off get the jumperpack"
still_walkin 
Silver - Posts: 644
Silver spacespace
Joined: April 18, 2007
Location: California, United States
Posted: February 26, 2010 at 5:34 PM / IP Logged  
It was the egr valve
1993 sdv
Alpine 4x6 6x9 5 1/4 swr-10d4
alpine v60
12.5 VGA flip down
Nettop pc w/10" touch screen
78nova
5-re audio 5x7 ,10" sub &
Xtx-500.5
"Take the faceplate off get the jumperpack"
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