car is throwing two codes, PO135- 02 heater (h+r - 11) CKT (b1, s1) and PO155 (h+r - 21) CKT (b2, s1)

the codes are for the front 02's, its both of them so i doubt theres actually something wrong,

does anyone know what fuse the front 02s run with? or anything else that could cause this?

 

bump. someone has to know something.

 

this might sound dumb put check the o2 sensors and clean them. might help.

 

Don't try to fix anything until you're sure the sensors are clean and working...

 

I say this all the time but check the trans harness for damage

 

Here's what the shop manual says about those codes...

All four O2 sensor heaters are powered from the same source, fuse #8 in the central junction box (under the dash).

 

sensors looked good a few weeks ago when i installed my O/R x, and i replaced the fuse today, light is still there and so are the codes, whats up with the trans harness? any other suggestions?

 

It is a power/wiring issue with the heaters for the front sensors, recheck the connectors...

Here's the wiring harness diagrams for the driver's side front (HEGO #21), and the two rear sensors; and the passenger side front (HEGO #11).

 

Its known to get damaged around the trans cross member... I've dealt with quite a few 02 sensor problems on mustangs and it has turned out to be harness damage.

 

alright thanks guys, will check into all that on my next day off