stevebez

OK, so I continue down this road of trying to find why my auto trunk system is not working anymore following a low battery and a replacement of the PDC controller.

So I continued to fiddle in the trunk and stumbled on an interesting issue. So when I nudge the large connector (I forget which direction but basically put pressure one way or the other) on the said control module the red trunk closing lights go off and then come back on if I release the pressure. So there is a short / dry connection somewhere at the mouth of the connector. I have searched everywhere else on the loom and cannot find any break in the wires especially the typical stress point just at the end of the arc of the trunk arm.

I cannot see any issue with the connections they all look in decent shape and if I wiggle the wire further from the actual connector the red trunk close / open lights stays on, so the bad connection / short is right by the controller unit.

So my question is ... do you think the controller is shot or do you think the controller needs some touch up on the contact solder points internally?

Dumb question but you know ... there is no such thing as a dumb question when it comes to these aging beasts.

machild

Connection issue could be on either the module or the connector. If you can get to the individual wires at the point of the connector and move them individually you may be able to repeat the connection break you saw and then know which connection is the issue. Then you can examine the two sides to see whether the connector is the issue or the module. A used replacement module is likely not much expense and may be a reasonable swap out to confirm. Good luck.

stevebez

Thanks !

Yes I tried the individual wire jiggle but that did not do anything I need to put light pressure on the entire connector. Seems the board / connector has a short, crack or dry contact somewhere. I'll re-solder the posts and try again and see if there is any difference and also check the connections by the switch. Interestingly, with the unit connected and I try to action the trunk closer I get no voltage out of the motor side. So either its not getting the signal or its fried.

machild

A diagnostic session with MB Star will tell you whether the car can communicate with the modlue, activate both opening and closing, and provide trouble shooting steps.

kevm14

Yes but if there is a break in continuity somewhere, it won't tell him if it's a broken solder joint on the module vs something wrong with the connector. But it would rule out some things at least. Playing swaptronics with the module (i.e. parts canon) would rule out a number of things assuming you have reason to trust the "new" module.

I guess one thing is to stick small pin into the particular connector pin that you distrust, and check for continuity somewhere down the harness. Do your wiggling and see if anything changes. If it's super rock solid on all suspect wires (or all wires) then it would probably be internal to the module.

stevebez

So tried again this morning after re-soldering the terminals on the controller and there was no response at all now, so pretty clear its fried - little strange that re-soldering the terminals killed it completely though.

I also pulled the Gateway out the car and took it apart as far as I could to see if there is any visible damage - and did see some water marking on casing but no damage internally AFAICS - its pretty much impossible to open up completely. All back in car, retried the trunk controller and still no life. Got a second hand unit on the way lets see how this goes. Not checked battery drain issue but I am pretty sure its the trunk unit.

On a side issue the cars tracker backup battery was dead and pulled that and will fit replacement today hopefully. Tracker people said the unit could drain the car battery some if the backup battery degrades - but did not say by how much. Its a 6V 1.2Ah battery ... so I doubt it would be a large parasitic load.

Edit: I checked each and every wire from gateway / switch to the harness plug and their continuity is all fine - it has to be the controller.

machild

Now that I have actually looked on eBay, these used modules cost more than I anticipated.

kevm14

What's wrong with this one?
https://www.ebay.com/itm/25481162941...wAAOSwxR1d79p1

About $72 shipped depending on where you are located.

machild

Are you asking me or @stevebez ? If you are asking me about the price I just thought they would be more the $35-40 range when I stated that I thought it would be easy money to swap another one in. When i did look I didn't really go any furhter than the $120 units. But, at a MSRP of $700, $72 is a good price.

stevebez

TBH I was surprised by the cost too - and availability - pretty much all from the USA. I got a trunk controller on the way for ~$130 after all duties and shipping. I can get a gateway locally for $60 shipped.

I don't think these trunk controllers are in production anymore.