Code reader question
 

The car is a '93CE, Federal version. I built the code reader as described on this forum and got a solid light (no blinks) on the LED. It was hooked up with the black plug on Pin 1 and the red plug on Pin 16 with the yellow plug on Pin 8. Got the same solid light on Pin 14.
Searched the forum but could not find any reference to this problem except a Radio Shack momentary switch being defective.
Any ideas?
Anziani

'93CE 170K
'95 E420 116K

Unplug the pin 14 lead and see if the light stays on. If so, miswired or the switch is shorted. If not, might be an issue with the car?

Jeff,
Without the test plug in 14, the light goes on or off depending on the switch. Am I understanding you that the LED should block any 12 VDC circuit and only blink from the test plug?
Anziani

The LED wires are not reversible - the red wire has to go to pin 16.

Yes,
The red wire goes to 16 and the black to pin 1. I'm going out now to check continuity on the switch. Perhaps it's bad?
Anziani

Test the tool :

Red wire on Battery Pos, Yellow on Neg...Led should light.

Red on Bat Pos, Blk on Neg , light should light only when switch activated.

Arthur,
The tool checked out perfectly per your instructions. I went back to the test with yellow pin on 14, black on #1 and red on #16. With ignition on, pressed the switch and got a solid red LED. Held it for 3-5 secs, closed switch and the LED went out. Did the same on pin #8, full red, no blinking, as long as the switch was energized. Does this mean that there are NO codes stored? Or am I a "blinking" idiot! I've lead a very technical life and this has me puzzled.
Anziani

Hold button for 2-3 secs for Diagnostics Initiation.... then codes will flash back.

Did you by any chance, use a momentary switch with NC contacts?

Arthur,
I have tried that. Held button for 3-5 seconds, then released it. Nothing. Does that mean there are NO codes?

Jeff, I used a NO/NC switch (RS 275-1565 and a 276-0270 LED) as shown in the forum schematic.
Thanks guys,
Anziani

I suspect you are holding the button too long.

Try 2 sec and then wait for the codes ..if there are NO codes , you should ge a single flash..

Finally figured it out. Was holding the button too long. Pulled 2 codes yesterday, cleared them. Will read again this AM to see what returned.
Thanks for the help.
Anziani

<Finally figured it out. Was holding the button too long. >

Post #8.

Checked today...NO CODES! I am a happy camper, except I noticed something strange: when the key is first turned and all of the panel lights come on, the lamp for the Snow Tire Switch was lit. That doesn't seem right to me.
Anziani

Nomal.