INT: Inoperable Power Door Lock Problem Solution

[deckeda]

I can also see how a bad solder joint could prevent a relay from clicking at all, possibly causing a misleading diagnosis of bad relay, bad lock switch etc. So it's nice to able to actually test that board all the way.

Nice DIY, fac90.

If something doesn't work, shouldn't it be replaced? fac90, can you clarify this statement here:

... This means the power door lock control unit is faulty, but may not need replacement. ...

Also, the PDF link 404'd for me; I found this by poking around: http://media.honda.co.uk/car/owner/m...400/16-228.pdf

The online manual is currently located starting here: http://www.honda.co.uk/car/owner/workshop.html

... and then the various links to the cars are javascript links Also, the '90 isn't included but much of this stuff is likely the same.

[fac90]

Was your door lock unit below the driver's seat? Mine was in the driver's door panel which made it a pain.

The actuators will probably be fine based on personal experience and your car is 2 years newer.

I think the easiest step would be to confirm the door lock unit is totally bad by checking the original circuit board for a bad solder joint, reconnect it, and test it. This is like the main relay problem with resoldering the connections.

Do you remember hearing a "clicking" sound when pressing the door lock switch? This sound (the black relays clicking on your board) cannot be heard when the actuators are activated by the unit.

There are 4 items here that will cause this headache:
a. door lock control unit (you can resolder some joints to fix it)
b. actuators (replace the bad ones)
c. door lock switch (replace the bad one)
d. Bad ground or loose wiring (unless it has been tampered with, not likely)