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Red light on!!!! 120-130 1965

HI,

After the SU flood I now have to turn to the electrics!!! So cool ;-) At least the car runs, so...

Ok the thing is when I drive at night & switch either the wipers, the fan, the turn signals, the OD (when the GB is in 4th) I get a very light illlumination of the charging light. When I say "at night" and "very light", I mean it probably does the same at daylight but I can't see it if it's not completely dark outside. Even city lights make it impossible to notice. The car's lights don't seem to be concerned since they won't light the red lamp.

I checked the tension, I get 14+ V at idle even with the charging light on, there is no short-circuit smell in the car (I'd notice, it almost burnt twice...) & the car runs smothely. When the engine is at high RPM, the light tend to get SLIGHTLY brighter. I thought of the fuse box but I have put an aftermarket one after I had several times the 25 amp fuse not getting any power, making the charging light go on & the OD disengaging while on the highway... I am very happy with this new item. I cleaned the connexions (acid spray) when intalling it.

Sooo... I have no clue about all this. HAve you any?

Thanks once again for your appreciated help!
Séb








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    Red light on!!!! 120-130 1965

    Séb;

    The AMP light being on slightly is NORMAL. It is caused by the voltage drop across the Fuse 1 resistance as current is drawn (V=IR, Ohms Law * ), and gets worse with time as additional resistance caused by corrosion at Fuse and ALL associated connections, increases this voltage drop.

    If you have replaced the fuseblock keeping the wiring of the new Fuse 1 the same as the original, you can expect to have minimized the AMP light glow, but that is NOT necessarily completely off, because there will still (and will ALWAYS BE) be a slight voltage across Fuse 1.

    Headlight current does not flow through F1 and so does not affect glow.

    If your belt tension and system voltage are OK, the (slight) increased glow at high RPM is very simply caused by the slight increase in voltage and therefore current...and so is normal and nothing to be concerned about!

    Your use of the term "acid spray" scares me! This MAY clean up corrosion temporarilly, but ANY acid used on electrical connections, especially if not properly and completely neutralized can and likely will cause new corrosion and problems. I highly recommend against it. Instead, I recommend the use of zinc suspension anti-corrosive paste on mechanically cleaned connections...you won't regret it!

    Read Gas-Tight-Joint article and other info on this exact subject at: http://www.intelab.com/swem/gastight.htm

    * Read about Ohms Law at: http://www.intelab.com/swem/an_automotive_electrical_primer.htm

    Cheers








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    Red light on!!!! 120-130 1965

    How's your engine-to-body grounding strap?
    I had a similar problem, but mine glowed a bit brighter than yours. After going round and round with electrical system diagnostics, I found out that with the headlights and fan on, there was .5v between body and block. One big ground strap later, it's a lot better....
    t








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    Red light on!!!! 120-130 1965

    How's your engine-to-body grounding strap?
    I had a similar problem, but mine glowed a bit brighter than yours. After going round and round with electrical system diagnostics, I found out that with the headlights and fan on, there was .5v between body and block. One big ground strap later, it's a lot better....
    t








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    Red light on!!!! 120-130 1965

    I have a simplistic approach to this problem. If high rpm makes the charging worse, perhaps the fan belt is slipping. The bolts underneath the original generator (if that is what you have) can loosen and deflect enough to lose belt tension, and the gen is very heavy, and these engines can vibrate a bit. I used nylocs(elastic stopnuts) on mine as a solution. Also, if your idle rpm is lower than spec, that light might glow dimly.








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      Red light on!!!! 120-130 1965

      Have you checked the condition of the fuse block? Sometimes they get pretty cruddy and need some repair. Dissemble the whole this (it takes a litle bit of drilling), clean all of the green stuff off, piece-by-piece and re-assemble. If you are good at soldering, tin and solder the whole thing so it won't happen again. I'm not good at that, but I recently did all the other stuff on the kid's '65 122 and it made all the difference in the world. It was amazing how cruddy everything was when I got it apart. It looked o.k. on the outside, but the hidden joints were a mess.

      It's possible to send the block to have it done, including ther tinning if you want it done professionally.

      Jim Hampton







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