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Author Topic: Measuring voltage in control box  (Read 5436 times)

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32ford

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Measuring voltage in control box
« on: 07, August, 2010 - 08:43:01 »
Hi

I recently posted about a problem with my display pod

http://c5alive.co.uk/forum/index.php?topic=1307.0

This weekend I have some time to try out my new multi meter, however, being a complete idiot when it comes to electronics, I have a few questions.

The c/box is still fitted to the C5. I really dont want to take it off unless I absolutely have to. When measuring the voltage, I assume I need the C5 battery connected, but do I need to also have the vehicle upside down and press the "go" button ? Or is there current flowing into the box just by having the battery connected ?

If the box needs repair (as in a blown resistor or whatever), does the box have to come off to do this repair, or can it somehow be done in situ ?

Thanks

Steve

Offline radiomarty

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Re: Measuring voltage in control box
« Reply #1 on: 07, August, 2010 - 09:30:44 »
Hi - you will need to open the bottom of the control box to get to the resistor / regulator Plod describes. Some are screwed together and some are heat sealed. It is possible to measure these voltages without pressing the button so no worries there - I will post a picture in a bit of where you need to measure across.You will be able to check with it in place but will need to remove it to fix it.Don't worry we will talk you through it.

Offline radiomarty

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Re: Measuring voltage in control box
« Reply #2 on: 07, August, 2010 - 10:08:44 »
OK photo time :



You wil need to put your negative probe from your meter on a 0v connection ie X1 the blue connection from the battery

1. First check you have 12V at R1 by placing your positive probe at point A on the photo.
2. Check you have 12v leaving R1 by placing your positive probe at point B on the photo - the other side of the resistor - if not you wil need to replace it.
3. If all ok with R1 check you have 12v going into the regulator by placing your positive probe on point D (ps I have removed the heat sink on this one for repair)
4. Now check the regulator is supplying the 5v you need by placing the probe on point C. You should read 5V if not the regulator will need changing.

Let us know how you get on

32ford

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Re: Measuring voltage in control box
« Reply #3 on: 07, August, 2010 - 10:13:04 »
Excellent. Thanks very much Marty. When I looked at the control box, I suspected there was something inside the bottom section, but mine has no screws, so I guess it is heat sealed. Whats the best way of getting it apart (and also sealing it back up) ?

Offline radiomarty

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Re: Measuring voltage in control box
« Reply #4 on: 07, August, 2010 - 10:16:07 »
Poss a sharpe knife - or sometimes the pull a part - best to get some small screws same as hold the t
op lid on to hold them back together.

Offline PLOD11

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Re: Measuring voltage in control box
« Reply #5 on: 07, August, 2010 - 15:23:25 »
I have a very large bag of those screws if you want some !!!!!

32ford

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Re: Measuring voltage in control box
« Reply #6 on: 08, August, 2010 - 11:11:50 »
I have a very large bag of those screws if you want some !!!!!

Sent you a mail Plod.

Offline coverman

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Re: Measuring voltage in control box
« Reply #7 on: 09, August, 2010 - 08:56:14 »
Hi, I just used a Dremel with a miniature grinding head to cautiously chew away the melted plastic seals in order to open the casing.

Offline POZE

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Re: Measuring voltage in control box
« Reply #8 on: 09, March, 2011 - 22:04:21 »
Hello
I'll be using this link more this weekend.
Ive already used it to replace the R21 in the pod, and today have seen that the R1 in rthe control box isnt giving out any voltage and looks burnt, so fairly safe to say that needs doing.

So hopefully i can get some pod lights on and the micro switch to work, so far i just havefront and rear lights.  Looking fwd to trying this all out over the wkend!  Cheers,