Code Scanner won't connect

[scsr_11]

1993 Eddie Bauer 4x4 4 door

Been trying to run down a very serious miss/lossofpower/bog. Couldn't find anyone to scan the codes for me so I got a code scanner from Oreilly's ($250 but returnable). I hook everything up and follow the directions on the screen. Simple. When its time for it to actually read the codes, it keeps saying "unable to read. check the cable, etc." Everything looks right. Anyone seen this bf?

I also got a diagram of the EEC plug and tried to get power to come from the bottom 3rd prong from the left (if you know what I'm talking about then you'll know what I'm talking about) with the switch on but got nothing?

I checked fuses but didn't see any related directly to this port.
Any ideas?

 

[MrShorty]

Having never tried using a scanner to get codes, I'm not sure all of what can go wrong between the scanner and the self-test connector.

I've always used a jumper wire to get the CEL to flash out the codes. My first suggestion would be to use this low-tech approach to see if the PCM can enter self-test mode or not. This will help determine if the problem is on the scanner side or the truck side of the connector.

 

[scsr_11]

Thanks for this suggestion. I searched and found a very detailed guide to get the codes via CEL. I'll give this a try this afternoon.