Volvo RWD 900 Forum

INDEX FOR 10/2025(CURRENT) INDEX FOR 12/2010 900 INDEX

[<<]  [>>]


THREADED THREADED EXPANDED FLAT PRINT ALL
MESSAGES IN THIS THREAD




  REPLY TO THIS MESSAGE    PRINT   SAVE 

horns not working 900

posted by  ajs on  Sun Jun 22 20:00 CST 2014
Author: [PROFILE] [EVERY POST] [THREADS] [BEST POSTS] RSS Feed     [IGNORE ALL POSTS]
last visit: Tue Jul 1 11:32 CST 2014
[RELATED]

1993T wagon. Old horns corroded and not working. Put in new ones… just a chirp (insufficient current getting through), not working really. Checked the buttons on the steering wheel..seemed ok. Jumper cable from the black/blue wire in the steering wheel to a good ground in the engine bay and the horns work fine.

Cannot find a circuit diagram with the black/blue lead. Can I assume the black/blue wire from the horns is continuous to the steering wheel area? If so, how is the horn button grounded? The jumper lead from the black/blue connection to the steering column provides the same 'chirp' but no real noise. Am thinking the steering column is not grounded properly, but do not know where to look.

I am flummoxed.
--
1993 940T wagon








  •   REPLY TO THIS MESSAGE    PRINT   SAVE 

    horns not working 900

    posted by  dinomartino on  Mon Jun 23 06:51 CST 2014
    Author: [PROFILE] [EVERY POST] [THREADS] [BEST POSTS] RSS Feed     [IGNORE ALL POSTS]
    last visit: Fri Oct 24 04:43 CST 2014
    [RELATED]

    If you have done any work inside the drivers side of the dashboard recently, remove the access panel on the top of the steering column and confirm that the little connector for the wire that runs up to the horns has not been tugged loose (or loose-ish) from the spade lug on the slip ring assembly.

    I failed state inspection 2 years ago because of that connection--installing the instrument cluster a week before had snagged the horn wire and tugged it just enough that it was loose on the spade resulting in no horn 95% of the time.

    and if you go chasing other faults, here are the relevant pages (90 & 91) from the green book to a 1993 940:




    I hope they are legible enough for your purposes...

    FYI, connector C2 is buried WAY THE F*%# up in the left hand side of the dash. Unless you show a lack of continuity between the connector at the horn and the connector at the slip ring, don't go chasing that connector.

    john

    --
    1989 245 245K / 1993 945 131K








    •   REPLY TO THIS MESSAGE    PRINT   SAVE 

      horns not working 900

      posted by  ajs on  Thu Jun 26 11:42 CST 2014
      Author: [PROFILE] [EVERY POST] [THREADS] [BEST POSTS] RSS Feed     [IGNORE ALL POSTS]
      last visit: Tue Jul 1 11:32 CST 2014
      [RELATED]

      SOLVED!!

      The root of the problem seems associated with my choice of horns. I used a couple of fiams which were for bmws- they were not new.
      I took apart switches and cleaned them up…put anti ox on all connections within the steering column, behind the air bag.

      The horns worked fine when checked using an external 12v source (a charger) but did not work in the car……until that is I fired up the engine. Now the horns work fine.
      So the horns do not work with the ignition turned on, but do work with the engine running.
      --
      1993 940T wagon








    •   REPLY TO THIS MESSAGE    PRINT   SAVE 

      horns not working 900

      posted by  ajs on  Mon Jun 23 11:49 CST 2014
      Author: [PROFILE] [EVERY POST] [THREADS] [BEST POSTS] RSS Feed     [IGNORE ALL POSTS]
      last visit: Tue Jul 1 11:32 CST 2014
      [RELATED]

      thanks for the tip on C2. I do indeed have continuity from the horn to the slip ring. in fact I do have a circuit, just not enough power...which makes me think that the grounding of the steering column is suspect. If I connect a jumper between the slip ring and a good ground the horns work.

      andrew
      --
      1993 940T wagon








    •   REPLY TO THIS MESSAGE    PRINT   SAVE 

      horns not working 900

      posted by  Amarin on  Mon Jun 23 10:23 CST 2014
      Author: [PROFILE] [EVERY POST] [THREADS] [BEST POSTS] RSS Feed     [IGNORE ALL POSTS]
      last visit: Thu Oct 23 22:42 CST 2014
      [RELATED]

      Hello,

      Referring to the diagram by dinomartino, component 6/1 is the windshield wiper motor. If your wipers are working, the horns are getting power. Check the grounding path.

      Hope this helps,
      Amarin.








  •   REPLY TO THIS MESSAGE    PRINT   SAVE 

    horns not working 900

    posted by  Steve on  Sun Jun 22 20:19 CST 2014
    Author: [PROFILE] [EVERY POST] [THREADS] [BEST POSTS] RSS Feed     [IGNORE ALL POSTS]
    last visit: Fri Oct 24 07:16 CST 2014
    [RELATED]

    https://www.brickboard.com/FAQ/700-900/ElectricalLightingHorns.htm#HornButtons

    Blue-black wire goes to a collector ring which in turn has a red wire to the horn buttons where the grounding occurs. I'll bet your horn buttons are corroded.








    •   REPLY TO THIS MESSAGE    PRINT   SAVE 

      horns not working 900

      posted by  ajs on  Mon Jun 23 05:18 CST 2014
      Author: [PROFILE] [EVERY POST] [THREADS] [BEST POSTS] RSS Feed     [IGNORE ALL POSTS]
      last visit: Tue Jul 1 11:32 CST 2014
      [RELATED]

      steve, now I think about it, I removed one of the horn buttons and shorted the two connections….same result, just a chirp from the horns……so I do not think the issue is the horn switches.
      --
      1993 940T wagon








      •   REPLY TO THIS MESSAGE    PRINT   SAVE 

        horns not working 900

        posted by  Steve on  Mon Jun 23 06:52 CST 2014
        Author: [PROFILE] [EVERY POST] [THREADS] [BEST POSTS] RSS Feed     [IGNORE ALL POSTS]
        last visit: Fri Oct 24 07:16 CST 2014
        [RELATED]

        There is a round collector ring in the steering column to which the black-blue wire runs. Current goes from there to the horn buttons via a red wire. Check that ring and wire. The horn buttons ground through the steering column itself. You may want to kludge a separate ground wire to the column to test this ground path








        •   REPLY TO THIS MESSAGE    PRINT   SAVE 

          horns not working 900

          posted by  ajs on  Mon Jun 23 09:36 CST 2014
          Author: [PROFILE] [EVERY POST] [THREADS] [BEST POSTS] RSS Feed     [IGNORE ALL POSTS]
          last visit: Tue Jul 1 11:32 CST 2014
          [RELATED]

          thanks again to the responses. The circuit diagram was better than the one I had.
          I believe the issue is the grounding of the steering column because as you put it "a kludge" from the horn button connector to a good ground makes the horns work (the current goes through the collector ring before getting to the horn switch).
          I have opened up the area (real PITA) by removing the knee bolster plate but still am unable to see where the grounding of the steering column occurs.
          --
          1993 940T wagon








    •   REPLY TO THIS MESSAGE    PRINT   SAVE 

      horns not working 900

      posted by  ajs on  Mon Jun 23 05:03 CST 2014
      Author: [PROFILE] [EVERY POST] [THREADS] [BEST POSTS] RSS Feed     [IGNORE ALL POSTS]
      last visit: Tue Jul 1 11:32 CST 2014
      [RELATED]

      that is helpful.
      I did look at the FAQ first, however I thought it unlikely that both horn buttons would fail at once (they seems to be wired in parallel).
      When I do depress the brass plate they do get very hot, even though I just get chirping from the horns, so there is circuit.

      Could not see how to take apart the horn buttons. Do I attack them from the brass plate side and pry off the brass plates?

      --
      1993 940T wagon







<< < > >>



©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.