Car comes to me, been looked at by someone else,
fault is intermittent MIL light, Fault code reads, Downstream O2 sensor short to positive.
The O2 sensor has been replaced by another garage, but obviously has not cured the fault, no fault no. given by Launch Diagnostics, wiring loom from sensor is visible ond in good condition, testing with meter from ecu does not reveal a short to positive, but putting Launch on Live Data shows sensor switching but switching up to 4.5mv, whereas upstream is showing normal at somewhere between .2 to.8mv, also adding to the confusion live data shows coolant temp at 140 and intake air at 100 degrees Centigrade, coolant temp gauge reads normal, so leaves me wondering if the Launch software is kidding me, or is the ecu for want of a better phrase is, buggering around, anyone out there seen this before, or got any thoughts on the subject p.s. forgot to mention the car seems to run and drive quite normally.