I have driven from Brussels to Wilhelmshaven to sort of my father-in-law's Volvo and there is a problem with the alternator. We fitted it and everything seems to work ok but the row of warning lights will not go out. The thing is, the old one had a blue wire and a red wire and then a small black box with a brown wire, this brown wire was fixed to a spade connector on the back of the alternator. The new one has the same but here, the brown wire is fitted to the same screw as the red wire. Could this be the problem? The spade connector on the alternator is there on the new one too but I did not change this as the new one came out a wrecked car (mine) and was almost brand new when I got it out. I just cut the cables and now, put the wires back as they were.

George,
you should have only three wires to the alternator, one a heavy red to the battery, a thin wire (probably red) from the warning light and an earth to the block.
Leave the thick red wire connected and disconnect the other two. With the ignition on, one of these wires should show battery voltage with a voltmeter.
this wire goes to the terminal on the back of the alternator.
the remaining wire is the earth and connects to one of the through bolts that hold the alternator body together and then down onto the block.
Good luck, Colin.

We do not have that third wire, something is wrong. Car has now been taken to dealer as I had to return to Belgium. I am very grateful for all your help, it pointed us in the right direction.
--
George Holmer, Belgium, Europe, 1987 745 GLE Turbo Diesel Intercooler (D24TIC/M46) 200k; 1988 745 Turbo Intercooler (B230FT/M46) 290k; 1988 745 GL (B200E/M47) 190k

Haroon is right. The alternator has three wires (assuming an internal voltage regulator) and they all must be OK for things to work.

The warning lights light up when their ground side is completed. If they are on the ground side is complete. When things work right, the only way that ground side can complete is through the alternator brushes.

That is the thin wire on the alternator spade connector. As soon as the alternator begins charging, that circuit is no longer a ground, so the lights go out. Then the little current that comes through the wire from the warning lights becomes the exciter voltage for the alternator.

What you have is a ground in that circuit in an unauthorized place. Result is lights never go out and alternator doesn't charge. Should be an easy fix.

The alternator is mounted on rubber bushings and thus must be grounded to the block. There is a wire from the alternator frame to one of the mount bolts. Be sure it's OK.

The charging current leaves the alternator through a stud connected heavy guage wire that goes to the starter, or maybe direct to the battery.

Hope this helps.

Good Luck,

Bob

:>)

I think you should wire your new alt the same way was the old one.

"The thing is, the old one had a blue wire and a red wire and then a small black box with a brown wire, this brown wire was fixed to a spade connector on the back of the alternator."

It's my understanding that the alt has three wires, a ground wire, a big red wire from the starter/battery and a small (usually spaded) small red wire that comes from the instrument cluster.

I think you should wire the brown wire to the spade connection as it was in original. The small box is a capacitor and newer models have it inside.

My 1990 B230F shows only a large and small red wire with a ground connection. You must have a different fitment.

Forgot, car is a 1988 740 GL with B200E engine, alternator is from car with B230E engine but Volvo lists the same part number for alternators on these two engines.