Help check engine light

I have a 1996 Jeep Cherokee classic, with a auto trans and a 4.0 engine. My jeep has 169,000 miles on it and it's still going strong. Today my check engine light came on and I retrieved two codes. On is a 36 and it's not listed in my hayness manual and the other is 55. My book said the 55 is "end of code output but what is a 36! Does anyone know what a 36!. Thanks for your time John

try rear o2 sensor?

Code 36 should be; Air switch solenoid circuit (non-turbo) or the waste gate solenoid on turbocharged models.
Here's a link to some of the codes,
http://go.jeep-xj.info/HowtoECUcodes.htm

I also have this same problem and I was wondering if anyone has any answers. I have researched the air switch solenoid circuit and I can not find any helpful information.

According to my code pulling software, the P0036 code is defined as HO2S Heater Control Circuit (Bank 1 Sensor 2). Further investigation defines this as the Heated Oxygen Sensor.

I think if it were me...I'd feel pretty safe in looking at that second sensor. The 55 is just telling you that that's all the codes in the ECU. Not sure of a test that can be done on the sensor but I also don't know if it's really worth the trouble. Haven't had the pleasure of doing that one yet.

-river

Thank you for the help, My jeep is a 92 and has only one Oxygen Sensor on the exhust down pipe before the cat do you think that code 36 still applies for my jeep.