Power Fold mirrors -- how do they work?

[star-art]

Guys, you'll need a factory wiring diagram for your year before trying to make a swap like this. I don't know for sure how much the wiring has changed, but from what I can see (I have 2009 and 2017 manuals), it's pretty similar overall.

First, you must have memory seats in order to install memory mirrors. There's no practical way to add a memory option (not saying it's impossible, just impractical). If you have memory already and want to add power-fold and auto-dim options, you must first verify that your year had a power-fold option available. If yes, then you need to swap out your power mirror switch and run some new wires to the Driver Seat Module (DSM). The DSM drives the mirror folding motors using input from the mirror switch.

If your year did not offer power-fold as an option, you can still add it but it will require some custom wiring such as adding a relay or using an aftermarket module to drive the mirror folding motors.

Again, the DSM controls the folding motors. A brief 12V pulse from the mirror switch triggers the module to fold/unfold the mirrors. The module "knows" how long to move the mirrors so they end up in the right position. One disadvantage to using a relay or aftermarket module is you might "over drive" the mirrors past their limits. This will still work, but it could cause added wear and tear on the folding motors.

The auto-dim function is controlled by the interior rearview mirror. If an auto-dim outside mirror was not an available option for your year, the interior rearview mirror might not have the additional output to drive it. In that case, it should be possible to swap your interior rearview mirror with a newer one that has the extra output to drive the auto-dimming driver's side mirror.

Hope that helps!

 

[The Wiped Cam]

@JollyRoger & @star-art

Thanks. Both of yous.

 

[TXFRDOwner]

To recap what Star-art said...

- Is it a simple plug-n-play mod? ................ No !

- Can it be done ? .......... Yes, with some basic understanding of wiring diagrams, automotive electrical skills.... and a decent amount of patience.

 

[The Wiped Cam]

Just came across this bizarre post over at the F-150 forum. The guy didn't have to run any additional wires in his memory-optioned truck. However, he ended up having to replace his DSM in order to make the plug n play install work I think I'm going to check to see if a Forscan flash + loaner mirrors + loaner switch will get me up n going. Might take me a month though to clear my schedule.

 

[TXFRDOwner]

Just came across this bizarre post over at the F-150 forum. The guy didn't have to run any additional wires in his memory-optioned truck. However, he ended up having to replace his DSM in order to make the plug n play install work I think I'm going to check to see if a Forscan flash + loaner mirrors + loaner switch will get me up n going. Might take me a month though to clear my schedule.

The big takeaway is being pre-wired !


Sent from my iPhone using Tapatalk

 

[star-art]

RE: The F150 post, this fellow was really lucky the wiring was already there. I don't know what year power-fold mirrors became available on F150. I'm guessing his Driver Seat Module (DSM) wasn't programmed for this option. Perhaps there's a line in the code to enable that feature? If so, he didn't really need to replace the DSM, just reprogram it.

On the other hand, if his DSM was not compatible with power-fold, he would've needed to upgrade it to a newer version.

 

[JExpedition07]

I believe 04 was the start. Let me check

 

[JExpedition07]

RE: The F150 post, this fellow was really lucky the wiring was already there. I don't know what year power-fold mirrors became available on F150. I'm guessing his Driver Seat Module (DSM) wasn't programmed for this option. Perhaps there's a line in the code to enable that feature? If so, he didn't really need to replace the DSM, just reprogram it.

On the other hand, if his DSM was not compatible with power-fold, he would've needed to upgrade it to a newer version (see below).

On our trucks, my 2009 factory wiring manual makes no mention of a power-fold option for either Expy or Navigator. The 2010 brochures say it was standard on Limited, King Ranch, and Navigator that year. So, it was available on 2010-17 models.

One thing I had not thought of until now:

If power-fold was not an available option for your year and you have memory seats/mirrors, you can't wire your power-fold mirror motors to your Driver Seat Module (DSM). It won't have the outputs to control the folding or the software to handle this functionality.

In this case, options are:

1) Use an aftermarket module or relay.

2) Replace your DSM with a 2010 or newer style that includes outputs for the power folding mirrors. Note that this will require custom programming through FORscan. It might also have unintended consequences due to changes in the programming and/or firmware inside the DSM.

The wiring book isn’t correct, Expedition Limited models have had Power-Fold mirrors standard since the 2004 model year

 

[TXFRDOwner]

RE:
On our trucks, my 2009 factory wiring manual makes no mention of a power-fold option for either Expy or Navigator. The 2010 brochures say it was standard on Limited, King Ranch, and Navigator that year. So, it was available on 2010-17 models.

Powerfolding wasn’t always controlled through DSM, I don’t know at what point Ford made the change but there was a much simpler setup before.

This little fellow right here, OEM Ford Relay 8C3Z-14N089-A aka the Power Folding Mirror Module

 

[star-art]

The wiring book isn’t correct, Expedition Limited models have had Power-Fold mirrors standard since the 2004 model year

You're right! The 2009 brochure mentions it and it is indeed in the 2009 wiring diagram. I stand corrected! Post above now edited.

Powerfolding wasn’t always controlled through DSM...

Well, that should make things easier! Use this module instead of connecting to the DSM.