If I understand what is going on, a light comes on on a scan tool and blinks a number of times. This indicates a voltage has been applied between two pins. If this is so, then a simple volt meter, analog or digital would be able to discern absence or presence of a voltage. Count the number of voltage spikes and you have the error code. Any comments??? Thanks

NO

You send an Initiation Signal to the ECU and it sends back it's memory storage in Flash Format , which is LED activation. { Square Wave]

Well, so much for that idea....thanks

Don't quit now , Gramps !!!!

You can make one for about $5 worth of parts from Radio Shack..

Here ya go..

http://members.aol.com/ajdalton7/ledtool.jpg

I have the device but I need a manual for the LEDs, Anyone have it?

__________________
Master Computer Engineer, A+, Network+, MCP/MCSA/MCSE 4/2k/2k3 - Messaging, MCTS, MCITP, MCT, Brainbench, ICDL and starting Ph.D

380SE 1984 <------- Totaled by flipping accident
300SE 1988 <------- Sold
Volvo S70 2000 <---- 4 family
Opel Omega 2002 <-- 4 family
560SEC 1989 <------ Sold
560SEL 1990 <------ Sold
560SEL 1991 <------ 4 my mother
560SEL 1989 <------ Sold
600SEL 1992 <------ Current

http://search.ebay.com/_W0QQsassZkhazenzcc

I've used my cheap digital multimeter to read codes when I didn't have an LED available. It was servicable, but it's much easier to count flashes than to study a digital display that is displaying all sorts of numbers. An analog meter would work fine.

Several years ago Arthur Dalton posted a link to a Baum scanner manual that lists codes. It has been uploaded and is available for download here: http://www.benzworld.org/forums/r129-sl-class/1266535-diagnostics-sl-pre-94-a.html?

I built a circuit that automates the process of reading and erasing analog codes. To read a code you momentarily press a button and the circuit counts the pulses and displays their total for you. It can also automatically read and erase all codes stored in a particular controller with just one touch of a button.

The circuit consists of two integrated circuits, three transistors, a two-digit LED display, and a dozen resistors. The cost is only about $10, but it takes some time and effort to solder it together. If someone is handy with a soldering iron and enjoys electronic projects, they may want to email me for details. But most people will want to use a Radio Shack 276-209 like Arthur uses in the circuit he mentions above.

Thank u very much

__________________
Master Computer Engineer, A+, Network+, MCP/MCSA/MCSE 4/2k/2k3 - Messaging, MCTS, MCITP, MCT, Brainbench, ICDL and starting Ph.D

380SE 1984 <------- Totaled by flipping accident
300SE 1988 <------- Sold
Volvo S70 2000 <---- 4 family
Opel Omega 2002 <-- 4 family
560SEC 1989 <------ Sold
560SEL 1990 <------ Sold
560SEL 1991 <------ 4 my mother
560SEL 1989 <------ Sold
600SEL 1992 <------ Current

http://search.ebay.com/_W0QQsassZkhazenzcc

That tool is for OBD1
You are asking for OBD2..that is completely different and is ISO/Digital Format.