Volvo RWD 900 Forum

INDEX FOR 10/2025(CURRENT) INDEX FOR 9/2019 900 INDEX

[<<]  [>>]


THREADED THREADED EXPANDED FLAT PRINT ALL
MESSAGES IN THIS THREAD




  REPLY TO THIS MESSAGE    PRINT   SAVE 

940 horn failure 900 1993

posted by  dinomartino on  Tue Feb 5 20:07 CST 2013
Author: [PROFILE] [EVERY POST] [THREADS] [BEST POSTS] RSS Feed     [IGNORE ALL POSTS]
last visit: Fri Oct 24 04:43 CST 2014
[RELATED]

I recently had my 945 fail VA state inspection for a non-functional horn. After testing the horns themselves and confirming they functioned, I then dug out the multimeter and started checking the wiring. COnfirmed 12.5V on the yellow wire at the horn connectors. Then I disconnected the battery to disable the SRS since I expected to be screwing with the steering wheel.

Then I checked for continuity between the blue/black wire (switched ground) and chassis ground--there was NO continuity when the horn button was depressed (none when it wasn't depressed, either, but that's NORMAL). So, that confirmed a problem on the switched ground side of the wiring. First I confirmed the un-switched side of the switches had continuity to ground, then checked the switched sides with the switches depressed. OK. So the problem was between switches and horn connectors. Joy. Based on the wiring diagram, I went in search of C2, a big black 52-connector plug which turns out to live inside the car, tucked way up under the dashboard along the inside of the fender. Found continuity between horn connectors and both sides of the plug, but NO continuity between the switched-side of the switches and the plug. So, the fault was between the switches and the connector. Removed the small access panel on top of the steering column, and discovered the slip ring contact was readily accessible. Confirmed continuity between switches and body side of slip ring, but none between slip ring and C2.

Turns out: there is a spade connector on the back of the assembly where the blue-black wire attaches to the slip ring. This connector had come loose (doubtless when I was removing and reinstalling the instrument cluster last week) creating the open circuit. SO, although the FAQ warns of melting horn switches and common sense warns of badly corroded connections at the horns, if your horn abruptly stops functioning--especially after you've done ANYTHING up inside the dashboard--get out a screwdriver and check the tightness of this simple connector. Because of its location it it highly vulnerable to being yanked loose.

john
--
1989 245 244K / 1993 945 129K








  •   REPLY TO THIS MESSAGE    PRINT   SAVE 

    940 horn failure 900 1993

    uid 6573's pic
    posted by  javalion on  Wed Feb 6 11:15 CST 2013
    Author: [PROFILE] [EVERY POST] [THREADS] [BEST POSTS] RSS Feed     [IGNORE ALL POSTS]
    last visit: Wed Jul 23 09:57 CST 2014
    [RELATED]

    1993 944, with horn problems every year. One true horn ring failure from a JY donation and later replaced with the original. Checked continuity as you have and couldn't find the problem. Reassembled and it worked but problems continued, remove the steering wheel check continuity, clean the horn ring reassemble and it is fine for a while.

    About the 4th or 5th steering wheel removal over a period of years I found the real issue, the black? wire that has sort of a flimsy spring open connection to the back of the steering wheel. I was able to remove it, open it up a little and push it back in. I didn't pay attention to it in the JY horn ring donation car but I still don't think this is what Volvo intended. It seems like there should be a spring, a rubber wedge, chewing gum, to keep the wedge open. The problem is solved for present time.

    I will look at that blue/black wire next time.

    Tom
    Among the news of the day, the US Post Office will discontinue mail delivery except for parcels on Saturday as early as August.







<< < > >>



©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.