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I'd say your numbers look good from the perspective of putting out plenty of voltage to recharge the battery - almost too good, but they look good. With an Alternator (not Generator) you shouldn't expect to see voltage >15VDC. That fuse displayed in the CSM wiring diagrams (which is supposed to exist) could exist anywhere on that red wire to be honest. Wiring diagram doesn't show location, only a point of reference relative to other wire(s) wiring.
Does the GEN warning lamp remain at the same brightness both when you turn the IGN SW to ON but prior to starting the car?
Does the GEN warning lamp remain at the same brightness when the car is started & running or does the GEN warning lamp change brightness depending on load of the vehicle i.e. while driving, increase in RPM?
Then GEN light has a constant brightness no matter what condition. If the key is turned to the “on” position, the oil and gen lights are light of course, and when the engine starts, the oil light goes out, and the gen remains on, same intensity; constant. I can rev the engine, doesn’t make a difference, the GEN lamp is on and never fluctuates.
Then GEN light has a constant brightness no matter what condition. If the key is turned to the “on” position, the oil and gen lights are light of course, and when the engine starts, the oil light goes out, and the gen remains on, same intensity; constant. I can rev the engine, doesn’t make a difference, the GEN lamp is on and never fluctuates.
That's good feedback. As you can witness yourself, the instrument lamp cluster contains the GEN warning lamp & oil pressure warning lamp. The fact the oil pressure lamp turns on/off indicates the oil pressure warning lamp & wire is continuous and operates normally. The fact the GEN warning lamp does not operate in a similar/identical manner provides more suspicion the issue resides on Brown wire or the circuit board where the Brown wire attaches. I don't think your issue demonstrates a faulty lamp/bulb in and of itself; but anything on that wire is suspect and of course that lamp/bulb resides on that wire - could the bulb be shorting out on the board? Heck, change the oil pressure bulb with the GEN warning lamp bulb see if it goes out.
The fuse is on the regulator. Delco part # 1945171. It attaches to the regulator B terminal and the battery wire attaches to the fuse. These were seldom replaced when the regulator was replaced or serviced. That is why you seldom see them anymore. This is a 30 amp fuse. There may be other sizes, but I'm not sure. Actually this might be a 60 amp fuse
That's good feedback. As you can witness yourself, the instrument lamp cluster contains the GEN warning lamp & oil pressure warning lamp. The fact the oil pressure lamp turns on/off indicates the oil pressure warning lamp & wire is continuous and operates normally. The fact the GEN warning lamp does not operate in a similar/identical manner provides more suspicion the issue resides on Brown wire or the circuit board where the Brown wire attaches. I don't think your issue demonstrates a faulty lamp/bulb in and of itself; but anything on that wire is suspect and of course that lamp/bulb resides on that wire - could the bulb be shorting out on the board? Heck, change the oil pressure bulb with the GEN warning lamp bulb see if it goes out.
Working under the dash is a pain! I was able to remove the GEN bulb and throw another bulb in its place; same result. GEN light on full strength. There is a wiring harness that attaches to that GEN/OIL/ CLUSTER/LEFT TURN SIGNAL bulb cluster. I did barely see a browin wire attaching to that cluster. I have to try and follow it further into the depths of wiring. I will try to remove that cluster but space is tight and working like this gets all the blood going to my head haha!
The fuse is on the regulator. Delco part # 1945171. It attaches to the regulator B terminal and the battery wire attaches to the fuse. These were seldom replaced when the regulator was replaced or serviced. That is why you seldom see them anymore. This is a 30 amp fuse. There may be other sizes, but I'm not sure.
Stellar, I don’t have a fuse on the VR. I will send a pic of what I have going on. The brand new one 35 amp made in USA VR I picked up today.
Where are the two red wires on the reg B terminal going? Pretty sure there should only be one wire there,.
one red wire BATT goes right to VR in first pic. Disregard that other red wire I am holding in picture #2, that is switched power wire that runs to en electric fan for the radiator.
If you have an electric rad fan, you may not want to lower the voltage any. I don't see the brown wire going to the center terminal. You are going to have to follow it, sorry to say. I also suspect it is grounded somewhere between the bulb and the terminal where it should be.Possibly someone thought it is a ground wire and grounded it to the body. Look around the regulator area. You may get lucky and find it attached to ground.
What is the wire with the red end about 3 inches below the reg and to the right attached to the body? Any chance it is brown? If you don't know what it is, take it off for a moment and see if the gen light works.
If you have an electric rad fan, you may not want to lower the voltage any. I don't see the brown wire going to the center terminal. You are going to have to follow it, sorry to say. I also suspect it is grounded somewhere between the bulb and the terminal where it should be.Possibly someone thought it is a ground wire and grounded it to the body. Look around the regulator area. You may get lucky and find it attached to ground.
I was able to remove the cluster the GEN / OIL light is on. When I probe the female end of the harness that you see in the first picture, with the key to the “on” position, my probe light is lit! All other female contacts on that harness do not light when the key is switched on. The female end of the harness is attached to the single brown wire, which runs to the right, under the dash somewhere. Does this mean that the brown wire is in fact grounded somewhere and that it is causing my GEN light? Have I pinpointed the wire and just have to see where the brown wire leads to and what is going on with its other end under the dash???
I was able to remove the cluster the GEN / OIL light is on. When I probe the female end of the harness that you see in the first picture, with the key to the “on” position, my probe light is lit! All other female contacts on that harness do not light when the key is switched on. The female end of the harness is attached to the single brown wire, which runs to the right, under the dash somewhere. Does this mean that the brown wire is in fact grounded somewhere and that it is causing my GEN light? Have I pinpointed the wire and just have to see where the brown wire leads to and what is going on with its other end under the dash???
I doubt you removed the cluster, I suspect you removed the connector. The brown wire is supposed to have voltage when the IGN SW is in the ON position and you already answered that question when Stellar asked you in Posts 24 & 25. This is not newsworthy, sorry.
We've been referencing a Brown wire from the very beginning. I think you've answered your own question.
The "point" here is the light should go OFF when the car is "running". Probing that Brown wire w/ the IGN SW in the ON position provides really no useful information. We'll spend a great deal of useless time determining where this issue resides if you don't follow the Brown wire. You have a wiring diagram - read it. Any additional wiring by anyone - all bets are off. This is why you follow a wiring diagram.
I doubt you removed the cluster, I suspect you removed the connector. The brown wire is supposed to have voltage when the IGN SW is in the ON position and you already answered that question when Stellar asked you in Posts 24 & 25. This is not newsworthy, sorry.
We've been referencing a Brown wire from the very beginning. I think you've answered your own question.
The "point" here is the light should go OFF when the car is "running". Probing that Brown wire w/ the IGN SW in the ON position provides really no useful information. We'll spend a great deal of useless time determining where this issue resides if you don't follow the Brown wire. You have a wiring diagram - read it. Any additional wiring by anyone - all bets are off. This is why you follow a wiring diagram.
I will you know what I find. Taking a break from this for a bit. I’ll continue to trace that brown wire to see where it leads. Thanks for all the patience and the help.
Addressing this w/ complete clarity & perfect resolve it shouldn't surprise you the vehicle was wired correctly when it left the assembly line. The wiring diagram demonstrates the correct wiring schematic. You want to know the absolute best way to resolve your issue? Disconnect any and all ancillary devices which were/are NOT germane (a part of) the original vehicle. Completely disconnect ALL of them. Get back to GROUND ZERO on the wiring diagram i.e. connect only the wires the car was born with. They're listed in the wiring diagram.
Addressing this w/ complete clarity & perfect resolve it shouldn't surprise you the vehicle was wired correctly when it left the assembly line. The wiring diagram demonstrates the correct wiring schematic. You want to know the absolute best way to resolve your issue? Disconnect any and all ancillary devices which were/are NOT germane (a part of) the original vehicle. Completely disconnect ALL of them. Get back to GROUND ZERO on the wiring diagram i.e. connect only the wires the car was born with. They're listed in the wiring diagram.
My car is pretty much unmolested. Thought a couple of pics from mine might help to compare. I noticed in the pic in #45 there's a wire grounded to the firewall and it looks like it is brown.
What is the wire with the red end about 3 inches below the reg and to the right attached to the body? Any chance it is brown? If you don't know what it is, take it off for a moment and see if the gen light works.
Originally Posted by Supernice88
My car is pretty much unmolested. Thought a couple of pics from mine might help to compare. I noticed in the pic in #45 there's a wire grounded to the firewall and it looks like it is brown.
That question has been addressed twice now. BTW, the wire looks black to me & it's completely unclear how or if it plays a role in this wiring configuration. Could be a ground for an amplifier in the shrunk for all we know at this point.
That question has been addressed twice now. BTW, the wire looks black to me & it's completely unclear how or if it plays a role in this wiring configuration. Could be a ground for an amplifier in the shrunk for all we know at this point.
On mine there are two brown wires attached to the middle post, his has been changed and I can't see where his are going. I thought maybe this ground wire could be the gen light wire.
I'm following along and I'm trying to learn too. Sorry if I had missed where that was discussed.
Last edited by Supernice88; Feb 10, 2024 at 05:44 PM.
Reason: add comment
My car is pretty much unmolested. Thought a couple of pics from mine might help to compare. I noticed in the pic in #45 there's a wire grounded to the firewall and it looks like it is brown.
What is only modestly interesting is to note you have two Brown wires on your Armature (middle) VR terminal - which I don't believe I've seen on the original GM Oldsmobile wiring diagram but is included on the B&W wiring diagram you posted earlier. I suspect the small Brown wire (of the two Brown wires) is for a condenser located somewhere on that little Brown wire as the symbol depicts a universal DC voltage condenser. Both (one located on the GEN & one located on the VR) would only be used for noise suppression.
On mine there are two brown wires attached to the middle post, his has been changed and I can't see where his are going. I thought maybe this ground wire could be the gen light wire.
I'm following along and I'm trying to learn too. Sorry if I had missed where that was discussed.
No worries - you're helping to address the issue. Your extra little brown wire from the VR (center) Armature post should lead to a condenser located on the generator.
Yowsers ---- let's hope that wire with the red end terminal connected to the metal firewall isn't connected to the GEN warning lamp.
No worries - you're helping to address the issue. Your extra little brown wire from the VR (center) Armature post should lead to a condenser located on the generator.
Yowsers ---- let's hope that wire with the red end terminal connected to the metal firewall isn't connected to the GEN warning lamp.
If I look at my wires they are going through the firewall to inside the car. I know about the ones on the generator. In the schematics they do show the brown wire forking off and it goes to the printed circuit board as the light.
That question has been addressed twice now. BTW, the wire looks black to me & it's completely unclear how or if it plays a role in this wiring configuration. Could be a ground for an amplifier in the shrunk for all we know at this point.
I really don’t know what the brown wire to the lower right of the VR is. I’ll undo and see what happens. It runs into the vehicle with the rest of the group of wires, going right to the fuse box.
If I look at my wires they are going through the firewall to inside the car. I know about the ones on the generator. In the schematics they do show the brown wire forking off and it goes to the printed circuit board as the light.
We're way past that point (Post 28)...we know the Brown wire leads to the GEN warning lamp on the board. You need to start reading further up.
I really don’t know what the brown wire to the lower right of the VR is. I’ll undo and see what happens. It runs into the vehicle with the rest of the group of wires, going right to the fuse box.
There are NO ground wires which ever lead TO or FROM a fuse panel - none, zero, zilch, nada. A fuse panel contains (+) wires - never (-) negative earth wires - never.
You had better start disconnecting wires, using masking tape/painters tape and clearly mark the purpose of each wire, place the marked masking tape on each wire.
There are NO ground wires which ever lead TO or FROM a fuse panel - none, zero, zilch, nada. A fuse panel contains (+) wires - never (-) negative earth wires - never.
Ok, the brown wire affects the GEN lamp. If that brown wire is grounded on the firewall like it was, the lamp STAYS lit. I unground it, and the lamp goes off. I need to check the wiring diagram to double check where that brown wire from the fuse box is supposed to run to. May be getting closer to figuring this out…
My car is pretty much unmolested. Thought a couple of pics from mine might help to compare. I noticed in the pic in #45 there's a wire grounded to the firewall and it looks like it is brown.
So what I can tell from the wiring schematic, the brown wire that was grounded on the firewall needs to connect to the VR where you’re does in the pic, then another brown wire on that same prong runs to the corresponding lead on the generator? Is this correct?
Connect that wire to the center terminal of the regulator and retest. See if light comes on with key on engine off and then start car and see if it goes out. test voltage at battery when running. I think you got it now.
The condenser on the reg and genny have no ground wire. The body of the condenser is the ground. The hot side of the condenser wire is only a couple of inches long. Supernice posted some very good pics to see the condenser on the reg. It also shows the fuse on the reg B terminal. His pic of the circled wire with the red end is what I was hoping was the gen light wire. Thanks Supenice for the pics.
The condenser on the reg and genny have no ground wire. The body of the condenser is the ground. The hot side of the condenser wire is only a couple of inches long. Supernice posted some very good pics to see the condenser on the reg. It also shows the fuse on the reg B terminal. His pic of the circled wire with the red end is what I was hoping was the gen light wire. Thanks Supenice for the pics.
The red tape on that ground got me thinking - why? When I zoomed in it looked brown. In the schematic the oil sending light is sharing the power with the gen light so when the wire got grounded it caused a fault and remained on. Why didn't the oil light stay on too?
different ground circuit. Oil light is either closed or open-on or off controlled by the oil pressure switch. Gen light has power flowing in both directions to the bulb. From ign switch through bulb to gen armature post and grounds through the generator ground brush when key on engine off. When key is on and engine running and genny is charging power is returning to the bulb. This gives you power at both sides of the gen bulb putting the light out (no ground) with balanced voltage at both sides of the bulb. A couple of volts difference at either side of the bulb (ign switch side or charging generator side) will allow the bulb to iluminate. This is why if the fuse is blown the gen lite won't come on in key on not running and the gen lite will come on when running and charging.
Not sure about the regs being good or bad. Probably have to try them all again to find out. Can you give the voltage of your car when running at idle and at higher RPM for him to compare his to? I would like to see his a bit higher than yours because he is running an electric rad fan.
Not sure about the regs being good or bad. Probably have to try them all again to find out. Can you give the voltage of your car when running at idle and at higher RPM for him to compare his to? I would like to see his a bit higher than yours because he is running an electric rad fan.
I haven't had it running since Monday, the battery was a little low. It was on high idle and was reading 15.17 and stayed around there even after it went to slow idle with everything turned on in the car. I didn't test it again after I went for a ride. I could check it again tomorrow.
I envy you guys. I have no idea how to post a good picture or how to put arrows and circles on a picture. I'm guessing you use one of the newer phones to do it. I have an old camera, an old computer an old phone and an old mind. Probably time to hang it up and let the enlightened ones run. Even when I tried to enlarge the diagrams all I got was a fuzzy picture. I should probably spend some time learning the new technology, but there is a saying about old dogs and new tricks. keep up the good work guys.
