Questionhi PAUL,hope YOU CAN HELP, ASTRA ENVOY TURBO DIESEL 1998, WHEN I DISCONECT WIRE FROM TEMPRETURE SWITCH,THE COOLING FAN COMES ON, WHEN I RECONNECT IT GOES OFF, IF I SHORT THE WIRES ON THE PLUG, THE FAN GOES OFF. QUESTION - HOW DOES THE SWITCH WORK, IS IT A HIGH RESISTANCE WHEN COLD, AND AS ENGINE HEATS UP, RESISTANCE DROPS, ALLOWING CURRENT THRU TO TRIP THE SWITCH? THE ENGINE NEVER OVERHEATS, BUT THE ENGINE WARNING LIGHT (ECU) ALWAYS LIGHTS UP WHEN DRIVING
AnswerHi Neil, if the light is on, it usually means a failed sensor (in my experience, it is ALWAYS the cam shaft sensor). Have a garage use a scan tool to tell you the problem. The CTS does work the way you think, but it would not put the ECU light on unless it had failed, in which case you would just replace it for a few pounds (£8-£12). The RAC & the AA both have the scanner which will tell you. If yu see a van belonging to one of these organisations, and you offer to re-numerate the gentlemen, most will be happy to check it out for you. - let me know and we can go from there. - Paul
