A place to discuss hardware/software and diagnostic procedures

test lights

More
4 years 2 months ago #36398 by tspinat
test lights was created by tspinat
I WAS WATCHING YOUR VIDEO ON TESTING IGNITION COIL PRIMARY CIRCUITS FOR B+ POWER AND - PULSE. WITH THE COIL CONNECTED.
Q: CAN YOU UNPLUG THE COIL CONNECTOR AND GO IN BETWEEN WITH A TEST LIGHT { LED OR INCANDESCENT } WHICH DO YO RECOMMEND ? OR LEAVE IT PLUGGED IN. WILL IN HURT THE COMPUTER? THANKS PAUL
The following user(s) said Thank You: aboudi.naddaf

Please Log in or Create an account to join the conversation.

More
4 years 2 months ago #36403 by Andy.MacFadyen
Replied by Andy.MacFadyen on topic test lights
Coils (and also normal fuel injectors) take a large curent and produce voltage spikes so you aren't going to harm the driver in the computer with any kind of normal wattage test light. With test light connected to ground check crank the engine and test both sides of the coil --- it should give a steady illumination on the 12v B+ side and on the control side flicker dimly as the engine is cranked.

" We're trying to plug a hole in the universe, what are you doing ?. "
(Walter Bishop Fringe TV show)



The following user(s) said Thank You: aboudi.naddaf

Please Log in or Create an account to join the conversation.

More
4 years 1 month ago #37064 by Tutti57
Replied by Tutti57 on topic Re:test lights
I hear all the time from people to not use a test light, but I don't understand how a circuit with a device that uses 5-10 amps can't handle less than 1 from a test light?

Nissan Technician
The following user(s) said Thank You: aboudi.naddaf

Please Log in or Create an account to join the conversation.

More
4 years 3 days ago - 4 years 3 days ago #38614 by Dtech494
Replied by Dtech494 on topic Re:test lights
I agree a test light wont harm the coil driver circuit or injector driver circuit.

But it is unlikely to show anything meaningful either if you are checking for a say a toggling 5v signal with a 12 conventional bulb.
Nor will the computer safe led test light of 20ma show you a faulty ground.
I believe a while back there were some current sensitive drivers in solenoid circuits such as purge, hvac control etc. But I personally doubt the 500ma from a test light would harm them. Not sure if there were any sensitive sensor circuits.
Keep in mind though if you put in a 98 marker bulb in your test light it actually sparks when you touch your connection.
Point is and more so for those who do not know is to understand the circuit before working on it and use the appropriate tool for the test in order to get the appropriate results while avoiding anything that may cause harm.

You did nothing wrong and unfortunately you may find certain techs that want to make themselves look good to others who do not know any better.
I find that when I do a different type of test or procedure than what they are used to that some one tends to have something to say. From my point of view they are wrong, from their point of view I am wrong. Gotta shake your head sometimes because it is simply over their heads.
Last edit: 4 years 3 days ago by Dtech494. Reason: Fix typos
The following user(s) said Thank You: Noah

Please Log in or Create an account to join the conversation.

More
3 years 11 months ago - 3 years 11 months ago #38819 by Tutti57
Replied by Tutti57 on topic Re:test lights
Dtech nailed it here. Some guys, instead of being open to learning something new, they say you're wrong. Particularly when you are talking about voltage drop tests vs ohms and activating circuits with a test light.

You could actually show them the amperage of your light and the amps of the load in the circuit, or the size of the fuse, but I've find that that ends up being a waste of time because they just understand the concepts.

Nissan Technician
Last edit: 3 years 11 months ago by Tutti57.

Please Log in or Create an account to join the conversation.

Time to create page: 0.232 seconds