Alarm/RS installers: what do you use to test?

[kpr10is]

On the maxima forums I frequent, there is an ongoing argument over what to use when testing wires for alarm/rs installs. So I figured I would post the question here. DMM vs test light? Anyone have any particular one they prefer?

In 4 years of doing them, Ive used a DMM most of the time with a probe that has a bed of nails on it so i can squeeze it to test individual wires without damaging the wire. Having such a math-based brain myself I feel like I'd rather see a number of voltage rather than listen for a beep or look at the test light to see what is lit up. But I feel like I'm one of the few, as most people I know use computer-safe test lights these days. Nothing against test lights, I've used them before and there are situations where they're nice to have, but I guess I've just built up trust in my fluke.

Discuss.

[BigDawg]

I love my Fluke87, but my SST test light gets used quite frequently as well.

[TJElite]

I use a DMM. Test lights are almost useless, and sometimes dangerous...read any newer car shop manual, and they warn against them. I once saw a guy launch an airbag by hitting the wrong wire with a test light.

Try and find a weak ground with a test light...

Toby

[kpr10is]

As far as the airbag...I wasn't meaning regular walmart $5 test lights, I was meaning the nice ones that are computer and airbag safe. My coworker has the Matco 42v and I know Snapon makes a similar one as well. The people who use them swear by them.

Diagnostics, Circuit Testers | Matco Tools Online Tool Catalog (http://www.matcotools.com/Catalog/toolcatalog.jsp?cattype=T&cat=2264&select=&page=5)

Not saying I disagree because I like my meter better as well Toby, just playing devil's advocate.

[Notladstyle]

^^ Ive got the power probe II - i wonder if its airbag safe...

Everyone warns against using a test light and everyone has seen someone launch an airbag with a test light.

On any 95+ car, all the airbag wires are isolated and are wrapped in red yellow or blue wire loom. If you launch an airbag using a test light you have to be totally incompetent.

a DVM is 100% PCM and BCM safe though so on newer cars with heavy computerization, it might be wise to use a DVM. But for a 10 year old toyota or honda, ford or other older vehicle, test light is faster and more convenient.

Being able to send pos and neg straight through your test lines or equipment without added wiring trouble is a must in some situations.

I would say a test light AND a dvm are required in any alarm installers tool bag. Even for alarms where I have all wires memorized, I still bring a test light just to ensure there are no wiring faults while the install is in progress.

[TJElite]

As far as the airbag...I wasn't meaning regular walmart $5 test lights, I was meaning the nice ones that are computer and airbag safe. My coworker has the Matco 42v and I know Snapon makes a similar one as well. The people who use them swear by them.

Diagnostics, Circuit Testers | Matco Tools Online Tool Catalog (http://www.matcotools.com/Catalog/toolcatalog.jsp?cattype=T&cat=2264&select=&page=5)

Not saying I disagree because I like my meter better as well Toby, just playing devil's advocate.

You got me there...I gave up on test lights years ago, and didn't realize that there were 'high tech' ones out. Still have to question why anyone would spend that kind of money on a test light, though.

I guess a light would be quicker for some things, and like Dalton said, for sending power or providing ground to a circuit, a test light works well. I've also used them for testing pulse circuits, where a meter can be too slow. But, for the most part, give me a DVM...

Toby

[TJElite]

^^ Ive got the power probe II - i wonder if its airbag safe...

Everyone warns against using a test light and everyone has seen someone launch an airbag with a test light.

On any 95+ car, all the airbag wires are isolated and are wrapped in red yellow or blue wire loom. If you launch an airbag using a test light you have to be totally incompetent.



I'm going back to 1991/92 time frame, when air bags were new, and the generic test light was still the weapon of choice. From memory, the car was a 91 camaro, and the air bag wires ran right with the other column wires. The tech said he wasn't even probing the air bag wire, but must have speared it by mistake.

I remember this big 'bang' followed by a tech crawling out from under the dash covered in white powder, and his own pee.

Toby

[kpr10is]

lol @ his own pee...

I don't own a probe, but two of my fellow installers have them, one with the Matco SST 42v which doesnt send voltage, and one with a Power Probe that does. If I really need to send voltage, I can move one of the leads on my meter to be common with the other lead, and touch whatever I need to. Providing ground would be helpful in some rare instances, but I've never felt one to be necessary. Ive never really seen the need for one, and I'm glad there are others that still feel the same way because I see more and more people use probes all the time.

[93ex]

I use a DMM, only because I dont have a test light. Sometimes I prefer the simplicity of a test light, others I need the numbers.

[Notladstyle]

lol @ his own pee...

I don't own a probe, but two of my fellow installers have them, one with the Matco SST 42v which doesnt send voltage, and one with a Power Probe that does. If I really need to send voltage, I can move one of the leads on my meter to be common with the other lead, and touch whatever I need to. Providing ground would be helpful in some rare instances, but I've never felt one to be necessary. Ive never really seen the need for one, and I'm glad there are others that still feel the same way because I see more and more people use probes all the time.

once you get used to sending voltage at the flip of a switch, you will never be without it.

[MCOR]

I agree. It is quite difficult to see a DVM readout when you are tucked under a steering colomn or twisted around a kick panel harness. A power probe is worth its weight in gold when the technician knows how to use it. Also, most installers that have been around can readily tell the difference between the brightly colored locking connectors of the airbag system and the normal connectors that the wiring needed for the alarm system will be located in. In my 12 years as a technician/shop foreman at the Ford dealership, I never saw a single airbag set off accidently by a technician, nor did I ever hear of it happening at any other dealer locally. But, there are differences between those doing this everyday and the hobbyist. I would suggest however if you are a novice, use the multimeter-can't hurt anything with that-keeps you 100% safe...

[lolsrc]

^^ Ive got the power probe II - i wonder if its airbag safe...

Everyone warns against using a test light and everyone has seen someone launch an airbag with a test light.

On any 95+ car, all the airbag wires are isolated and are wrapped in red yellow or blue wire loom. If you launch an airbag using a test light you have to be totally incompetent.

a DVM is 100% PCM and BCM safe though so on newer cars with heavy computerization, it might be wise to use a DVM. But for a 10 year old toyota or honda, ford or other older vehicle, test light is faster and more convenient.

Being able to send pos and neg straight through your test lines or equipment without added wiring trouble is a must in some situations.

I would say a test light AND a dvm are required in any alarm installers tool bag. Even for alarms where I have all wires memorized, I still bring a test light just to ensure there are no wiring faults while the install is in progress.


some new benz dont have there airbag wires marked. dmm ftw

[Notladstyle]

some new benz dont have there airbag wires marked. dmm ftw

I would never install a remote start in a benz - thats just murder.

But yes there are some higher end jags and Mercedes vehicles that aren't labeled. But thats the exception, not the rule. And even then, they are still ran through independent harnesses

[GradeA_TireFryer]

i saw an installer pop a bag also in a camero but he was upside down with legs in seat - pop goes air bag- 1 broken leg! - then i had to finish and fix the car! - that powder gets on everything!

[lolsrc]

I would never install a remote start in a benz - thats just murder.

But yes there are some higher end jags and Mercedes vehicles that aren't labeled. But thats the exception, not the rule. And even then, they are still ran through independent harnesses

agreed remote start in a benz is just murder!!