> wrote in message
...
> On Apr 25, 10:42 am, "Mike" > wrote:
>> > wrote in message
>>
>> ...
>>
>> >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.