Check engine light with O2 codes after both sensors have beenreplaced

I have a 2001 Chrysler Town and Country Limited (3.8 L) with 122K
miles on it. A few months ago the check engine light came on and
there where three codes 1684 (battery disconnect) , 1491 (radiator fan
relay) and 0135 (O2 sensor). Two weeks ago I replaced both O2
sensors. After driving the car for a few miles the check engine light
went off. A couple of days ago it came back on and the same three
codes are back.

Are the O2 sensor I put in bad or is something else wrong?

Thanks in advance,

Derek

 

The P0135 code is O2 sensor heater circuit - bank 1 sensor one. You did
check the heater circuit before you replaced the sensor, right ????

 

Uhhhh -seeings as how I don't know what you are talking about the
answer is clearly no .

How do you 'check the heater circuit'?

 

You need to check for power and ground on the wires going to the O2 heater.
You will need a wiring diagram and a multi-meter to check for power and
continuity. You could check all the fuses as the power to the heater should be
on a fuse. I don't know which fuse it would be but just check them all and
replace any that are blown.