The 3-4 shift 'is directly controlled by the hydraulic circuits in the valve body.'

It does say to check engine speed (tach) sensor, pressure switch assembly, brake switch, system voltage and TCC solenoid.

You'd have to pull the pan to check the solenoids and switches - you'd be measuring resistance.

 

a 1995 blazer with a bad shift seleniod would thorw a check engine light, no need to drop the pan and check ohms.

 

That depends if he has OBD II, OBD 1 or OBD 1.5.

 

if its a 95 then their is no way it has OBD1, 1994 was the last year for OBD1 in the S10 blazer, It has OBD 1.5/2 so it will set a code if their is a problem with the shift seleniod or circitry.

 

Wrong!

Besides, I have changed solenoids to fix transmission shifting issues where there were no stored OBD2 codes on a few different vehicles.

 

^ thanks, Kyle.

 

Just found out the guy I bought it from removed the bulb from the check engine light, I replaced it and it is on. The ECM is mounted on the the passenger side fender, the decal says it is OBD1 and the connector is OBD11 but looks like it only uses 5 pins. I am assuming it is the dreaded OBD1.5, how do I pull codes from this before I pull the tranny?