Volvo RWD 900 Forum

INDEX FOR 10/2025(CURRENT) INDEX FOR 3/2003 900 INDEX

[<<]  [>>]


 VIEW    REPLY TO THIS MESSAGE Replies to this message will be emailed.    PRINT   SAVE 

rear window heater - voltage at terminals? 900 1993

Can anyone tell me what they're getting as a voltage reading betweeen the rear window heater terminals? Mine doesn't seem to be heating that well, and the voltage between the terminals at each end is only 9.8 volts. All my voltage readings were taken with the ignition on and the engine not running, but this still seems a bit low.

I've made the following additional voltage measurements (I used the metal ring on the ignition key cylinder as a convenient ground; that may have impacted on the voltage values):
- 11.5 volts at dash switch/relay input with heater off
- 10.8 volts at dash switch/relay input and output with heater on (this seems to indicate there is no loss at the relay)

I'm surprised that there would be a .7 volt drop on such a short run to the switch/relay. It suggests that there's a relatively high resistance connection somewhere from switch/relay to fuse panel to battery. Does anyone have wire routing/connection details for the rear window heater on a '93 940 so I can trace it through?
--
David Armstrong - '86 240(350k km?), '93 940T(270k km), '89 240(parts source for others) near Toronto






THREADED THREADED EXPANDED FLAT PRINT ALL
MESSAGES IN THIS THREAD

New rear window heater - voltage at terminals? [900][1993]
posted by  darmstrong  on Fri Dec 29 06:15 CST 2006 >


<< < > >>



©Jarrod Stenberg 1997-2022. All material except where indicated.


All participants agree to these terms.

Brickboard.com is not affiliated with nor sponsored by AB Volvo, Volvo Car Corporation, Volvo Cars of North America, Inc. or Ford Motor Company. Brickboard.com is a Volvo owner/enthusiast site, similar to a club, and does not intend to pose as an official Volvo site. The official Volvo site can be found here.