horn relay needed? '95 camaro

Hi, Can I trigger the horn on a '95 Camaro with the low level - horn output from a Viper alarm or do I need to add a relay? Thanks. -Andrew

is it just a straight negative trigger horn? if so it'll do just fine.A DMM is a beautiful thing.

MECP Advanced Installer Certified.

Test by going to the horn wire in the steering column. do you have a DMM? Set to DC amps current range, black probe to ground, red probe to wire. Horn should sound and your display should give you the current draw. If 120 milliamps or below, the neg output is fine.

Thank you Mr H. I get concerned when I see the device and its "signal" treated as one & the same - ie, the horn's current as opposed to its relay's trigger current. Though I suspect the jargon means the "control" so that starter inhibits etc NEVER refer to the starter's current.... In which case I hove novices understand that.

You and I realise that but WTH!

Oh poo - now we've alerted them.... Some have already noticed my omission of "the obvious" in some posts. They suspect it is to provide more income for professionals (installers etc). But some pros suspect it's more money for product suppliers because although they are paid for the jobs, they aren't necessarily professional.... I can't win - except by not helping. Nah - you're right - WTH? It's only money. (PS - how did I hove novices understood instead of hope they do, er, did. v & p are far from adjacent (it's not not a Dvorak kyb).)

Let's face it I could probably ground that wire directly and see by how big the spark is whether or not it needs a relay. Don't try that at home kids. Also assuming it's a neg going wire (I can't think of a horn push type that isn't). Do they realise that older cars didn't have a relay? The horn had a constant pos feed and was grounded through the push so one would go about this by ascertaining if there's a factory relay. If there is then it's safe to ASSUME that the wire in the steering column is only a low current trigger.

howie ll wrote: Do they realise that older cars didn't have a relay?

Sorry mate - I had Jap cars. (Relays in our 1964 cars.) But agreed - many were hot (as today) but with horn button grounding; hence the popular 3-terminal hot relays (86 internally connected to 30) with their though BHS (Battery Horn Switch) labels. Mind you, we didn't have headlight relays though I always retrofitted mine - at least for inner spots, and halogens. But some cars only started with them some decade or 2 ago. Mind you, I know of mid-late 1980s Jap vehicles with a relay for headlight power, yet the beams are grounded thru the beam and dip switch; I never could quite figure that one out (omit the relay else add another relay). But stop here - you may get me started on "battery isolation switches" on the hot side that do NOT isolate the alternator because people think they should also kill the engine. (IMO - with rare exceptions - isolate and kill should be kept separate, hence enabling ground isolation rather than dragging hot & unfused cables diagonally through a car! Crazy isn't it?!)