Those readings kinda scare me. We hope the 17 volt reading is a typo.

I can't help with the specifics of how to set up your Sperry but the 20V range would be correct, just be sure you're measuring volts, not ohms, milliamperes or hertz or something. Use the negative post of the battery for the black lead of the meter--connect it there. Measure the positive post. You should see 12.5 V thereabouts. If you follow the smaller red wire from that post you'll come to a black terminal box and right next to that is the 25A fuse that partly makes bricks what they are. It is exposed to a lot of weather and wasn't built for it, so some of us replace the fuseholder with a waterproof version. It is the only blade type automotive fuse in the vehicle.

Once you've verified the meter is doing good for you (12V at the battery), keep the negative meter lead connected to the battery minus post and take your AMM voltagereadings. The white wire should be close to 0V. The orange should look like the battery, 12.5V. The red/white is the key to its function and should read around 1.6V. The yellow wire could read anywhere from zero to about 2.7V. It is the result of an adjustment. And the remaining two wires should be very close to zero; they are ground wires for the AMM.

I think I remember there are some tips for using multimeters in the "general mechanics" section of the 700-900 FAQS.

Let us know how you make out!



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Art Benstein near Baltimore