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Re: Engine fault codes procedure

Posted: Fri May 01, 2020 2:24 pm
by beegee
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Re: Engine fault codes procedure

Posted: Fri May 01, 2020 2:32 pm
by Micron
Yeah, I think that's what I have too.

Re: Engine fault codes procedure

Posted: Fri May 01, 2020 3:36 pm
by Jon G 24V
I have old Analoge Meter that I use for exactly this Job. Just set it to 12 VDC Range on the same Pins as you'd put the LED on, put the Link in and away you go.

You just count the Sweeps instead of the LED Flashes to determine the Code.

No advantage with either if you ask me, I just use the Meter as I had an old one spare 😎😎

Re: Engine fault codes procedure

Posted: Fri May 01, 2020 4:50 pm
by jrh
No, the resistor is in series with any 'leg' of the LED. The purpose is just to limit the current draw to a tiny amount under any circumstances.
Some 'cheap' voltmeters can impose a significant load on the circuit ( that needle doesn't move by magic ! ).

Re: Engine fault codes procedure

Posted: Fri May 01, 2020 5:21 pm
by Sunfly
Jon G 24V wrote: ↑
Fri May 01, 2020 3:36 pm
I have old Analoge Meter that I use for exactly this Job. Just set it to 12 VDC Range on the same Pins as you'd put the LED on, put the Link in and away you go.

You just count the Sweeps instead of the LED Flashes to determine the Code.

No advantage with either if you ask me, I just use the Meter as I had an old one spare 😎😎
Thanks Jon, that's put my mind at rest.

Re: Engine fault codes procedure

Posted: Fri May 01, 2020 5:26 pm
by Sunfly
jrh wrote: ↑
Fri May 01, 2020 4:50 pm
No, the resistor is in series with any 'leg' of the LED. The purpose is just to limit the current draw to a tiny amount under any circumstances.
Some 'cheap' voltmeters can impose a significant load on the circuit ( that needle doesn't move by magic ! ).
Thanks for that info John and I take your point about the meter and that was also my concern, however, now the beast has arrived, it does give the rating of the meter itself which is 1mW and 600ohms so I think that should be OK at 1mW, especially now Jon tells me he uses an analogue meter.

Re: Engine fault codes procedure

Posted: Sat May 02, 2020 8:47 am
by jrh
That's good Bob, just the needle 'flickers' to decode now.

Re: Engine fault codes procedure

Posted: Sun May 03, 2020 1:27 pm
by Micron
I found my code reader, and see that it has a 100 ohm resistor attached to the + leg of the diode.

Just tried it on the MX-5, no codes 8-)