I have a seat leon mk2 with no crank, no start, no ECU communication. Turning the key does nothing, no response from the car. Recently had 4 glow plugs replaced as well as injector #4, car stopped working after parking the car. I have tested the following:
- I have removed the starter relay and checked if its clicking, checked continuity between 30 and 87 and checked resistance between 85 and 86. all fine.
- I have removed other relays under the steering wheel, tested them as above and they are all fine.
- Tried to find 5V reference from the ECU, but instead found 0.19V volt in two connector places. One fuel related other not sure.
- one connector is fully covered in something (last picture below). when i inserted needle inside it came out black. i believe this is turbo related sensor.
- I have checked all fuses under the hood as well next to the steering wheel and all fine.
- Unable to read error codes as the computer connected via the OBD port is able to communicate with all modules except the ECU.
- Removed the ecu, tested the grounds going in to the ECU via ECU Connector A on PIN 1,2 & 4 and they are fine.
- checked all ground points i could find and they are fine.
- checked the voltage going through the PIN A 92 in ECU connector A (R1 Main Relay): 0.25V
- checked the voltage going through the PIN A 46 in ECU connector A (R4 Fuel Pump Relay): 2.8V
- could not detect any voltage going through the PIN 3, 5 or 6 in ECU Connector A
- removed the starter and it works as expected outside of the car
- when feeding the starter battery voltage where ignition signal would go the car attempts to crank, but does not start (even with easy start spray)
- engine not seized & starter confirmed working
- ignition switch does send out the signal as I've tested one of the switches going out of it when the key is in start position and I read battery voltage when turning key to start position.
- ignition voltage (pin 1) & battery voltage (pin 16) present in the obd port
- the starter relay R1, does not receive voltage on pin 87 at all. Grounds on 85 & 86 are fine. Battery Voltage present on Pin 30.
- there is no fuel going through the fuel rail to the injector 1 while attempting to start the car (while cranking). unscrewed the connector pipe to injector 1 and there is no fuel coming out.
Based on the above, is it safe to assume that ECU is potentially the culprit in all of this? I am detecting strange readings on ECU Connector A Pin 92 and 46, but I am actually unsure what they should be. It's either cable fault going to the ecu or the ecu itself. Any hints and tips regarding this issue greatly appreciated.
- I have removed the starter relay and checked if its clicking, checked continuity between 30 and 87 and checked resistance between 85 and 86. all fine.
- I have removed other relays under the steering wheel, tested them as above and they are all fine.
- Tried to find 5V reference from the ECU, but instead found 0.19V volt in two connector places. One fuel related other not sure.
- one connector is fully covered in something (last picture below). when i inserted needle inside it came out black. i believe this is turbo related sensor.
- I have checked all fuses under the hood as well next to the steering wheel and all fine.
- Unable to read error codes as the computer connected via the OBD port is able to communicate with all modules except the ECU.
- Removed the ecu, tested the grounds going in to the ECU via ECU Connector A on PIN 1,2 & 4 and they are fine.
- checked all ground points i could find and they are fine.
- checked the voltage going through the PIN A 92 in ECU connector A (R1 Main Relay): 0.25V
- checked the voltage going through the PIN A 46 in ECU connector A (R4 Fuel Pump Relay): 2.8V
- could not detect any voltage going through the PIN 3, 5 or 6 in ECU Connector A
- removed the starter and it works as expected outside of the car
- when feeding the starter battery voltage where ignition signal would go the car attempts to crank, but does not start (even with easy start spray)
- engine not seized & starter confirmed working
- ignition switch does send out the signal as I've tested one of the switches going out of it when the key is in start position and I read battery voltage when turning key to start position.
- ignition voltage (pin 1) & battery voltage (pin 16) present in the obd port
- the starter relay R1, does not receive voltage on pin 87 at all. Grounds on 85 & 86 are fine. Battery Voltage present on Pin 30.
- there is no fuel going through the fuel rail to the injector 1 while attempting to start the car (while cranking). unscrewed the connector pipe to injector 1 and there is no fuel coming out.
Based on the above, is it safe to assume that ECU is potentially the culprit in all of this? I am detecting strange readings on ECU Connector A Pin 92 and 46, but I am actually unsure what they should be. It's either cable fault going to the ecu or the ecu itself. Any hints and tips regarding this issue greatly appreciated.
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