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What causes the C1401 high pressure return pum code to come up on my 2002 ML 320? Lights on dash are on & it sounds like some or other pump is running blelow the windscreen washer bottle. Have had to disconnect the battery to get it turned off.
This code is informing you for short or open circuit.
Hi and Welcome to just answer< I am Pavlin. I will do my best to help you.
clcik here -left rear of engine compartment.
So far I do not see your reply
the code you have is for shorted or open circuit to ABS control unit.
and that is why pump is working all the time
I am sending you info to trace circuits, this is the way to fix this problem
What needs to be done to rectify the problem or does the pump have to be overhauled or replaced?
click on the first link I have sent to you please
there is the problematic circuit to be tested
it may be just wiring, or one of the units to be faulty
But wiring must be inspected first, as it may only be corroded wire or connector