Which OBD scanner?

[Laney760]

gpl1968 knows how to make them and gives a parts list here, I expect he posted the thread on how to make one somewhere

Originally Posted by gpl1968

Yes the push button starts the process. It works in the same way as with the OBD box that was in the engine bay of earlier 940s. Just follow the instructions in the FAQ.

I believe it has to be an LED to make the circuit work as it only allows current to flow in one direction (I suppose you could use a bulb and an appropriately rated diode, but that would be even more complex).
if you get a 12v rated LED you are also saved the task of adding resistors in series to protest the LED.

I made a parts list for an earlier posing. If it helps here it is:

Maplin
Small Narrow Box-------FT31J----£1.59
Rotary SW12B----------FF73Q----£1.79
Grn Mom Push Switch---N02AR----£1.99
12V Orn Plas Pan LED---N03BB----£2.19
Multi-Core 9-Way-------XR27E----£2.54
Knob RN15 Red---------FE76H----£0.79
Open Grommet 0705----QT93B----£1.79

ECUfix.com
OBDII Plug--------J1962 16-Pin Male----£2.49
Delivery--------------------------------£3.50 approx

Apart from the OBDII plug, which I found online, The rest of the parts came from Maplin.
I just found a shop assistant and we went through my rough list. My final choice was dictated by what was in stock as mush as aesthetics.
I could probably have used cheaper components and got a similar result.

[Laney760]

Found his instructions

Originally Posted by gpl1968

As long as you can solder and drill holes, it's easy.

You need:

An OBD plug. I got one here

The other components I got from Maplin (my choice criteria depended on form and function):

1 x metre length of data cable (min 5 core).
1 x rotary switch (min. 4 position) and knob
1 x momentary action push button switch
1 x 12v panel mount led
1 x enclosure (box)
1 x grommet (to protect the cable as it exits the box)

You need to check the wiring of the OBD socket in your car but, depending on it's spec, the pin designation should be:

1, ignition
3, fuel
4+5, ground (they are already connected in the plug)
12, ABS
13, cruise control
16, +12v



From the photo:
Red wire = +12v > +ve side of led
Green wire = common terminal on rotary switch > +ve side of push button switch > -ve side of led
Black wire = ground > -ve side of push button switch
Connect pins 1,3,12,13 to outer terminals on rotary switch

I hope this makes sense.

[Laney760]

Originally Posted by Laird Scooby

T
Good to see you back on, i hope your lurgy has gone!

Cheers Dave. I am off down the M4 to Wiltshire shortly, expecting to break down, see my thread :-)

[loki_the_glt]

Originally Posted by Laney760

Theres a thread in this section somewhere showing you how to build one cheaply. I bought mine from a forum member who made a load for forum members, it was very cheap, about £11 if I recall in about 2012/3?

That's inflation for you - I'm charging £20 for them nowadays, mainly thanks to Royal Mail's pricing.

If anyone IS looking for one I have all the bits available to produce 3 at present; that's becasue I only have 3 metres-worth of cable on hand.

[Piet22]

All you really need are a 12 Volt led and an extra piece of wire or an open paperclip.



Push the positive wire of the led in pin 16 of the OBD connector.

Push the negative wire of the led in pin 1 (for ignition error codes) or pin 3 (for fuel error codes) or pin 12 (for abs error codes) or pin 13 (for cruise control error codes) of the OBD connector

Push one end of the extra wire or the open paperclip in pin 4 or 5 of the OBD connector.

Connect the other end of the extra wire or paperclip to the negative wire of the led for one second.

The led should now give the error codes

[gpl1968]

I think I spent £17 on parts for mine some years ago, but that was when Maplin was open and I only had to order the OBD2 plug online.

Yes, you can do tests with an led and paperclip but it's much easier to just plug in the tester and not have to worry about which pin is connected.



One thing I would do differently though, is move the led into the space between the button and the knob. That way it would sit better in your hand when testing.
Still works though.

[Daver007]

Has Anyone got a code reader for a 940 for sale
Tia
Dave

[Laird Scooby]

Originally Posted by Daver007

Has Anyone got a code reader for a 940 for sale
Tia
Dave

Speak to Loki_the _GLT, you'll have to go into the Lounge section and get your post count bumped so you can send him a PM about it first though.

[loki_the_glt]

Originally Posted by Daver007

Has Anyone got a code reader for a 940 for sale
Tia
Dave

PM sent, with payment and email contact details.