check engine light
 

[:'(]My check engine light came on recently. Scaned, P1135 A/F sensor heater circuit malfunction (bank 1 sensor1) Changed MAF sensor this didn't solve problem. Checked heater relay OK voltage at sensor. can anyone help find the problem.

RE: check engine light
 

This is A/F s(02) sensor heater problem. The sensor heater current is too high or too low. This indicates an open or shorted circuit or bad heater.

RE: check engine light
 

;) It was my understanding this heater was located in the mass sensor this why i changed the sensor. I guess I need to find the wiring diagram.

RE: check engine light
 

MAF has a heated wire sensor but if the problem another code would have set.

RE: check engine light
 

The 1135 code specific for an A/F (02 sensor).

RE: check engine light
 

These A/F sensors also have a heater! The typically have 4 wires running to them.

RE: check engine light
 

2 for the heater circuit, 2 for the sensor. All are contained in the housing.

RE: check engine light
 

If you have an amp meter can the current draw of the sensor. Below 0.2 and above 8A is bad.

RE: check engine light
 

The AutoZone website may have diagrams.

RE: check engine light
 

toyomoho,
You are right! Took my meter across O2 heater ciricuit and it was open. Also found out O2 sensor and it was open might be covered under emission warranty(8 year 80,000 miles) I'll call toyota tomorrow THANKS!