CEL??? on and off? - Toyota Yaris Forums

beaker · 09-16-2014, 07:58 PM

Check your wiring at and around the O2 sensors where you were working. Make sure you didn't pinch a wire, or scrape some insulation off of a wire that may be intermittently touching bare metal. Shorted wires will cause crazy stuff.

2nd, put a scanner on it to get the code it is throwing. That way you'll at least have a starting point. A lot of today's scanner have troubleshooting info in them that will give you tips as to where to start looking for the problem. If you don't have access to a better scanner with troubleshooter info, go to Autozone, they can at least put a generic OBD2 scanner on it to pull a P code.

09-16-2014, 07:58 PM	#7
beaker Drives: 07 Yaris 3 door Join Date: Feb 2013 Location: conyers ga Posts: 87	Check your wiring at and around the O2 sensors where you were working. Make sure you didn't pinch a wire, or scrape some insulation off of a wire that may be intermittently touching bare metal. Shorted wires will cause crazy stuff. 2nd, put a scanner on it to get the code it is throwing. That way you'll at least have a starting point. A lot of today's scanner have troubleshooting info in them that will give you tips as to where to start looking for the problem. If you don't have access to a better scanner with troubleshooter info, go to Autozone, they can at least put a generic OBD2 scanner on it to pull a P code.