Voltage Regulator

[Cyclone101]

Hey guys, just a quick question.

My voltage is reading about 14v @2000rpm, but at 2500(ish) it drops back to 12v constant up the rev range.

I'm guessing my regulator is no more. Am i wrong? Is there a way to test a regulator?

Regards

Jacques

[Mike87]

Your voltage should stay at 14 through the rev range. Check the regulator and the alternator.

 

Look in the articles section for a charging system article. It will guide you though your troubleshooting.

Edited December 31, 2013 by Mike87

[adawil2002]

Bad voltage regulator. Do you have the Haynes manual?, Page 141.

 

Unplug the voltage regulator and with a piece of wire, bridge the blue and black cable pins of the plug.

 

Start the engine and run at 1000 rpm, if the warning lamp goes off immediately, you have a defective voltage regulator. If the lamp remains lit or glows dimly, then the alternator is at fault.

 

Voltage regulators are readily available from your preferred vintage BMW parts dealer or ebay.

[saaron]

Make sure you get the right voltage regulator...you need the one that the mounting point (where the voltage regulator is screwed into the body) is metal.  Otherwise you will have grounding gremlins.  Ask me how I know. 

 

Scott

[schoir]

 

Bad voltage regulator. Do you have the Haynes manual?, Page 141.

 

Unplug the voltage regulator and with a piece of wire, bridge the blue and black cable pins of the plug.

 

Start the engine and run at 1000 rpm, if the warning lamp goes off immediately, you have a defective voltage regulator. If the lamp remains lit or glows dimly, then the alternator is at fault.

 

Voltage regulators are readily available from your preferred vintage BMW parts dealer or ebay.

 

 

Using this testing method, are there results that would indicate both a good voltage regulator and a good alternator?

 

Regards, Maurice.

[Hans]

AS far as I know, the test for a voltage regulator is by voltmeter. It should show about 14V.

[adawil2002]

Using this testing method, are there results that would indicate both a good voltage regulator and a good alternator?

 

Regards, Maurice.

If your 'L' light goes out just after startup both should be fine.

[jp02ti]

check the ground strap from battery to block.  this looked like a bad regulator on the ti but once the new strap was in all my electrics issues dissolved.

[Napes]

Regarding your ground strap(s) it helps to periodically, say once a year, to remove them and place them in a container of baking soda and water mix.  Let 'em soak for an hour, or more, and they will usually come out all shiny clean.  Works for me.

 

Bob Napier