I am currently setting out to figure out how to add factory front and rear park assist. I've spent quite a bit of time researching and looking through the upfitters manual to try and figure out if and how I might accomplish this. I can say that this is a very expensive and time consuming upgrade....especially since both front and rear bumpers need to be replaced. There are several parts that need to be added and quite a few circuits that need to be added. From looking at my X61A junction box, there are several circuits missing, and I have confirmed that the park assist module and cluster will need to be programmed after exchanging emails with WAMS (White Auto Media Services). We are both unsure if the BCM will require programming. I am thinking that it may not be necessary for this mod.
2018 Silverado, Crew Cab LT All-Star Edition 5.3L
13447860 Control Module
19115653 Connector (You Wont Believe how expensive this is...but it comes with pre-terminated leads)
15127038 Connector & Terminal Part #: SAIT-A03T-M064
13525987 Connector & Terminal Part #: SAIT-A03T-M064
23145170 Stab Control Switch (Dash Switch to add park assist button) Terminated Lead Part #: 13575782
84029812 Front Bumper w/Fog Lights w/Sensors
84153946 Front Sensor x4
23276805 Park Sensor Bracket Front x4
23108141 Rear Bumper w/Sensors
23428268 Rear Sensor x4
23276807 Park Sensor Bracket Rear x4
The bumpers are very expensive as you can imagine, so I am still trying to source new OEM chrome bumpers. I may break down and buy OE replacements on Ebay as they are much cheaper. Same part numbers are used.
Circuits Needed to be Added:
3140 - Battery Positive Voltage
5852 - Rear Park Assist LED Disable Signal
5060 - Low Speed GMLAN Serial Data (I believe this circuit may already exist. Need to verify)
2751 - Signal Ground (This circuit may already exist under the passenger seat)
2375 - Left Rear Corner Object Sensor Signal
2376 - Left Rear Middle Object Sensor Signal
2374 - Object Sensor Control
2378 - Right Rear Corner Object Sensor Signal
2377 - Right Rear Middle Object Sensor Signal
2379 - Object Sensor Low Reference
5213 - Front Parking Left/Right/Mid Sensor
5215 - Front Parking Left Corner Sensor
5216 - Front Parking Left Mid Sensor
5214 - Front Parking Sensor Low Reference
5217 - Front Parking Right Corner Sensor
5218 - Front Parking Right Mid Sensor
Various Colors of 22 awg cross-link TXL Wire
1/2 in wire loom
Tesa Wire Loom Harness Tape
Replacing the front bumper is pretty straightforward and is laid out very well in Phil Gamboa's youtube video. The harness' will need to be replaced with the parts listed above. I recommend swapping out the harness' while the bumpers are off.
The rear bumper is a pain. You will need to loosen 8 bolts that attach the bed to the chassis. There are a few videos on how to do this. The bed does not need to be removed - It can either be propped up inside the wheel wells or held up by 2 people on either side while the bumper is lifted off. The bed needs to be lifted in order to fit the bumper brackets underneath it when pulling away from the vehicle.
You can replace the brackets and plastic parts on the rear bumper. It is pretty straightforward. Just squeeze the tabs one by one with a pair of pliers and they will release. If you pry the top plastic step without squeezing the tabs, you may break off the tabs.
Front Park Assist Sensors:
Phil Gamboa has done a great job showing how this is performed in his youtube video that shows him adding front park assist
Rear Park Assist Sensors:
Phil Gamboa has done a good job on explaining how to add front park assist. A nearly identical process is required to add the rear but instead the circuits will go to the X138 Connector under the hood and can be lead into the cab on the driver side much like how PGamboa did on the passenger side for the front sensors. From the upfitters manual it looks like the rear sensor wires go from sensors->harness->X185 Connector->X138->X2 Control Module Connector. I have not yet been able to locate the X185 Connector (most likely under the bed somewhere), but think that I will end up bypassing it and going straight to the X138 connector.
Control Module X1 Connector to Instrument Panel:
The X1 Connector Circuits will run straight to the X61A Junction Box under the driver door sil. Power and Ground from the X1 Connector look like they will run up the passenger door sil. Circuit 3140 - Battery Positive Voltage Lands in the X51R fuse block in the X1 Connector, in cavity #43. I landed the Ground lead using a ring terminal under the B pillar. There is a ground bolt down there.
Finding where exactly to land circuit 3140 - Battery Positive Voltage.
Circuit 3140 actually lands in the X51R fuse block. X1 connector, terminal #43.
Finding terminals for connectors has been very very difficult and I am still looking for several different types.
I am having a difficult time finding the correct terminals for:
S45A Multifunction Switch -> Ended up purchasing the GM terminated leads. Part #: 13575782
X61A Junction Box X1 Connector -> Mouser Part #: 829-35031567
X61A Junction Box X5 Connector -> Mouser Part #: 829-35031567
X150 Connector Male -> Mouser Part #: 571-964265-2-LP
X150 Connector Female -> Mouser Part #: 571-964263-2-LP
X901 Connector Male -> Mouser Part #: 538-33000-0002-LP. After landing the terminals, I cannot get the connector to seat properly and lock, but I have confirmed that all wires have continuity through the connector. I am still working on figuring out why this is happening.
X100 Connector Female -> Mouser Part#: 538-33012-2003-LP
Any help with figuring out terminals for where to find decently priced bumpers would be appreciated.
I am continuing to work on the project as time permits.
I am almost done with the modification as of now 8/27/19. I am waiting on a few park sensors to arrive to replace a few bad ones that I ended up with. I am getting a "Service Park Assist" Message on my cluster. I will follow up after I have this resolved to confirm everything is working as it should.