Circuit board trouble shooting fault.

[Buddylove]

Hi,
I have a control box which works stand alone or with additional box connected.
In standalone mode when the unit is switched on H is displayed in the screen.
If additional box is connected and unit is switched on X is shown in the screen. My problem is the unit does not see the box when connected and as a result shows H all the time. I have what looks like a RS232 cable that connects the unit to the box. What test can I do to see if the signal question is being sent from unit to box then signal answer from box to the unit. Failing that I will be looking for advice where the circuit board could be checked out.
Many thanks from a newbie.

 

[Tha fios agaibh]

I'm probably not the only one who has no idea what your talking about.

What kind of control box?
What is "H"? What is "X" what screen?

Manufacture? Model number?

 

[Buddylove]

It's was a generic explanation of the issue I have.

 

[davenn]

Hi Buddylove
welcome to EP

It's was a generic explanation of the issue I have.

that doesn't help us help you
you need to be specific, else it doesn't mean anything to any of us

cheers
Dave

 

[Buddylove]

It is a key programmer and decode box.
If Key programmer is switched on in stand alone mode H is shown on screen.
Connect the decode box and switch on key programmer screen should display X but it doesn't as H is shown.
Key programmer does not report back that decode box is connected.

 

[davenn]

still too non-specific
Do you know what the "H" code means ?, have you tried to find out ?

Again as was asked a way back ...... Manufacture? Model number?

Dave

 

[Buddylove]

H informs user that it is in stand alone mode.
X indicates user decode box is connected.
No model sorry.
I understand it will help you but don't have it. This is why I was thinking if signal is going to the decode box in first place and if so was signal being sent back. Just trying to narrow down the issue.

 

[Buddylove]

No signal to decode box then programmer has an issue.
Or signal to decoder is ok but no signal to programmer then decode box has an issue.

Can we trick the programmer into thinking the decode box is connected just to see if H display is changed to X when switched on.
Connect 2 pins etc to make a bridged connection ?

 

[Tha fios agaibh]

Would this be an automotive smart key programmer for a car?

 

[Martaine2005]

Buddylove.
All programmers and decoders have serial numbers for obvious reasons!
Car key CLONERS are specialist tools. You should contact the MLA here in the UK.
It must have a Model and/or number on it!

Martin

 

[davenn]

and on that note

thread closed
not much that can be done with something that is unknown