Hi, i have a lx470 from 1999 and recently the ahc is not working. It is showing the off light.
i have started replacing the following parts.
all accumulators.
Complete pump assembly incl all switches
All 4 shock looking things (the ones that raise or lower the car.
Relay for ahc.
all 3 height sensors.
So i kinda changed everything.
the error codes i keep getting and can not delete because they are instant back are:
C1743 main relay, but its new. I even changed it again just to check.
C1761 ahc ecu malfunction.
Note that all this started as following. Ahc has always worked. But 1 day some month ago when i stopped the car i was hearing the ahc pump buzzing.
The pump started buzzing every time when i stopped the car and pulled the key out of the ignition. Key in ignition pump did not make noise.
Key out, pump started running and kept running.
I thought. Ok the pump is on its end so lets buy all complete new.
New pump installed, and it did the same, same noise also.
So after that i installed all new. And never got the ahc working again.
car has 0 rust. All fuses are fine. And ahc ecu looks brand new both sides.
Door signal works on all doors. Same as ahc control switch. Checked all on active data with obd while running the car. Height sensors give data while driving. But 0 pressure readings.
I can manually in obd activate all relays and they click. But Errors stays.
i have started replacing the following parts.
all accumulators.
Complete pump assembly incl all switches
All 4 shock looking things (the ones that raise or lower the car.
Relay for ahc.
all 3 height sensors.
So i kinda changed everything.
the error codes i keep getting and can not delete because they are instant back are:
C1743 main relay, but its new. I even changed it again just to check.
C1761 ahc ecu malfunction.
Note that all this started as following. Ahc has always worked. But 1 day some month ago when i stopped the car i was hearing the ahc pump buzzing.
The pump started buzzing every time when i stopped the car and pulled the key out of the ignition. Key in ignition pump did not make noise.
Key out, pump started running and kept running.
I thought. Ok the pump is on its end so lets buy all complete new.
New pump installed, and it did the same, same noise also.
So after that i installed all new. And never got the ahc working again.
car has 0 rust. All fuses are fine. And ahc ecu looks brand new both sides.
Door signal works on all doors. Same as ahc control switch. Checked all on active data with obd while running the car. Height sensors give data while driving. But 0 pressure readings.
I can manually in obd activate all relays and they click. But Errors stays.
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