Five days ago, I ran into another AHC woe. The system went down to L, with AHC light blinking. I also discovered that the AHC fuse in the engine bay had broken - suggesting a short circuit somewhere. I was later to find that the AHC pump motor was the one causing the short circuit.
Having had quite a few episodes of AHC woes before, this time I was prepared to try to handle the repair work myself. FYI, I am nowhere close to being a mechanic. I am just a computer programmer. However, I have learnt a lot of mechanics by seeing and reading.
All I needed this time was to get a simple auto wiring technician around to assist me with a few things like testing and removing AHC motor/pump, etc. This person would now be my assistant in the task ahead.
So, yesterday - without Techstream - I had to diagnose the problem by connecting E1 and Tc on the DLC1 connector inside the engine bay. I have always done this, so no fuss here. And by the way, I have also ever used E1 and Tt for Transmission diagnosis.
I got DTC 62 and made reference to the code list below - suggesting that there was Fluid pressure malfunction (pump does not supply fluid).
62 - Fluid pressure malfunction (pump does not supply fluid)
61 - ECU malfunction
51 - Continuous electric current to the ahc pump motor
43 - AHC main relay malfunction
41 - Short circuit in AHC motor relay circuit
18 - Open or short circuit in pressure sensor circuit
or 11, 12, 13 for - Open or short circuit in the height sensors
So, now we opened up the pump assembly and confirmed that the pump motor was indeed causing a short circuit. I had an old spare motor, so we easily replaced it.
But the AHC system still failed to work even after replacing the motor, still throwing DTC 62. It was a struggle, but long story short, we decided to do what I had always feared most - disassempling and cleaning the AHC pump. I had observed that process being done a few times before, so I decided it is time for me to go bare knuckles.
You can't believe how simple it was to disassemble, clean and reassemble the pump. True to expectation, we found the pump (especially the filter area) quite dirty. We cleaned it thoroughly.
Fitting the pump back and starting the car, everything worked like a charm! I could not believe it, but here we are.
In all, we spent about 6 hours because it was a learning exercise. I am confident that I can take less that 1 hour to do the same next time.
Having had quite a few episodes of AHC woes before, this time I was prepared to try to handle the repair work myself. FYI, I am nowhere close to being a mechanic. I am just a computer programmer. However, I have learnt a lot of mechanics by seeing and reading.
All I needed this time was to get a simple auto wiring technician around to assist me with a few things like testing and removing AHC motor/pump, etc. This person would now be my assistant in the task ahead.
So, yesterday - without Techstream - I had to diagnose the problem by connecting E1 and Tc on the DLC1 connector inside the engine bay. I have always done this, so no fuss here. And by the way, I have also ever used E1 and Tt for Transmission diagnosis.
I got DTC 62 and made reference to the code list below - suggesting that there was Fluid pressure malfunction (pump does not supply fluid).
62 - Fluid pressure malfunction (pump does not supply fluid)
61 - ECU malfunction
51 - Continuous electric current to the ahc pump motor
43 - AHC main relay malfunction
41 - Short circuit in AHC motor relay circuit
18 - Open or short circuit in pressure sensor circuit
or 11, 12, 13 for - Open or short circuit in the height sensors
So, now we opened up the pump assembly and confirmed that the pump motor was indeed causing a short circuit. I had an old spare motor, so we easily replaced it.
But the AHC system still failed to work even after replacing the motor, still throwing DTC 62. It was a struggle, but long story short, we decided to do what I had always feared most - disassempling and cleaning the AHC pump. I had observed that process being done a few times before, so I decided it is time for me to go bare knuckles.
You can't believe how simple it was to disassemble, clean and reassemble the pump. True to expectation, we found the pump (especially the filter area) quite dirty. We cleaned it thoroughly.
Fitting the pump back and starting the car, everything worked like a charm! I could not believe it, but here we are.
In all, we spent about 6 hours because it was a learning exercise. I am confident that I can take less that 1 hour to do the same next time.
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