At 02:18 PM 10/8/2006 -0400, John Runberg wrote: >- grounds on both sides appear OK. Tested left high-beam on right >ground and OK, left on right + fails. >- removed all wired from the plugs and inspected. Look OK >- voltmeter shows 12v on left side, and that or slightly higher on >the right (why would it be higher??) >- meter I have can't check amps so I'm sidelined until I can get one. John, you have a total of about twelve volts distributed along the entire length of the headlight circuit from battery + through the wires and panel and switches and more wires and lamp socket and lamp and socket again and ground wire and chassis and back to battery --. Use your voltmeter from one part to another and discover where the "missing" voltage is that should be appearing across the lamp filament. You don't need/want an ammeter for this. The voltage in the circuit is distributed in proportion to the resistance in the various parts. The lamp filament is *supposed* to have the highest resistance in the whole circuit by two orders of magnitude or so, so that almost all the voltage will appear across its terminals and almost all the power dissipated in the circuit will go to blinding deer instead of melting terminals and such. But tiny resistances are hard to measure, so you turn the vehicle into a giant high-current ohmmeter by measuring the voltage drops instead... david
-- David Beierl - Providence RI USA -- http://pws.prserv.net/synergy/Vanagon/ '84 Westy "Dutiful Passage," '85 GL "Poor Relation" |
Please note - During the past 17 years of operation, several gigabytes of
Vanagon mail messages have been archived. Searching the entire collection
will take up to five minutes to complete. Please be patient!
Return to the archives @ gerry.vanagon.com
The vanagon mailing list archives are copyright (c) 1994-2011, and may not be reproduced without the express written permission of the list administrators. Posting messages to this mailing list grants a license to the mailing list administrators to reproduce the message in a compilation, either printed or electronic. All compilations will be not-for-profit, with any excess proceeds going to the Vanagon mailing list.
Any profits from list compilations go exclusively towards the management and operation of the Vanagon mailing list and vanagon mailing list web site.