This Cadillac CTS was in excellent condition but it did have an intermitent engine light which keeps on appearing when the vehicle is driven. With our scanner we can also find previous history saved codes within the verhicles ECU.
We found 2 fault codes. 1 would have caused the engine light and the other was a simple oil pressure sensor which was at fault, giving an intermitant voltage to the engine ecu when the engine was running. We used the Auto Sim Pro to confirm the wiring going from the wiring harness plug back to the ECU is OK and there was no breaks or shorts within the wiring harness. With the Auto Sim Pro we can make the engine ecu believe there is a sensor plugged in and test the voltage ranges with our diagnostic machine. The main fault which caused the engine light is the fuel tank pressure sensor. This is a part of the EVAP system and with this constantly giving the ECU a 5V reference it will trigger a fault code / light as a warning for this system.
Sadly due to the location of the Fuel Tank Pressure Sensor the customer will need to get the fuel tank dropped / removed for us to carry out furher checks on the wiring / sensor. With our advanced automotive testing tools we can give the customer a 100% answer rather than a typical garage guessing what part is causing the fault.
Need correct automotive diagnostics carried out on your vehicle? Call 07340 341790.