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Past 2 years, my R231's trunk will intermittently not open during cold spells below 60F. Using the interior or foot switches was an exercise in futility. Only by pulling the trunk switch/handle twice or more in rapid succession would it open (or use a key). It's not the struts as when it's open, it stays open. No sagging. We're now in the middle of a cold snap here in Houston TX. 1st one this season. The trunk is now totally inoperative. Only way to open was to use a physical key. The culprit is the Truck Lock Actuator Motor PN #231 700 00 85. Fits all R231s. The actuator contains a couple of microswitches. I believe over time, the microswitch springs get weak and is unable to function.
I scoured the internet looking for a reasonably priced actuator. Best price was MB of Warrick. $489.52 on Amazon Marketplace. Easy 45min job.
-- Lower top and open trunk. This is so the flaps fold outwards to expose felt trim push pins.
-- Disassemble the actuator decor panel and trunk felt trim which is held in place by a bunch of push pins. this will expose the actuator and the key tumbler. See photo.
-- Don't forget to disconnect the light, close switch and emergency trunk open.
-- Undo 2 torx screws holding the actuator to the trunk.
-- Remove key tumbler by unscrewing one torx screw and rotating counterclockwise. This needs to be done as there is a cable from the tumbler to the actuator that will need to be removed. See photo.
-- Reassemble in opposite order.
Fleabay is full of used trunk actuators for super cheap (below $100) or aftermarket Chinese knockoffs. Do not be tempted. Just buy OEM new and get it over with.
Last edited by TheWuMan; Nov 23, 2022 at 04:38 PM.
Great write up. I completely concur as I had to do the same repair last year. HOWEVER, I did not have the bright idea to fold the top and open the trunk and thus had to struggle with the flap linkages to get to the push pins!!
Great job! Thanks
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