I am working on a 96 Paseo 1.5 L engine. Replaced O2 sensor. 4 wire I can see signal on signal wire. The heater wires sides I see no reistance when cold. With power on no start. I see 12.4 volts on one wire for heater when I gound it to the block. If I attach meter to the ground wire of harness I only see .34 volts.

Does anybody have pinout for ECU. Also are these readings normal. You can drive the vehicle .7 miles or 56 miles but eventually the code P0135 will trip.

Help

FYI Fixed problem found that the signal and ground wire on universal O2 sensor were backwards