Bulletin No.: PIC6312C
Published date: 01/14/2020

Preliminary Information
PIC6312C 2018 - 2020 CT6 Super Cruise (RPO UKL) Diagnostic Tips
Models
Brand:
Cadillac

Model:

Model Years:

CT6

2018 - 2020

VIN:
from
All

Engine:

to
All

All

Transmissions:
All

Involved Region or Country North America
Additional Options (RPO)
Condition

UKL
Diagnostic Tips for Super Cruise Unavailable or Service messages.

Cause

To assist in quicker diagnostics due to new technology.

Diagnostics:
General Information/Notes:
-When programming, program both Active Safety Control Modules (ASCM) to avoid Full Speed Range Adaptive
Cruise Control (FSRACC) & normal cruise control mismatch
-When key cycling car to let every module shutdown properly, allow 5 minutes with the vehicle being o to
ensure all modules completely shut down.
DTCs:
-Do not act on DTCs in history, allow DTCs to retest to con rm whether an issue is present. (SI provides
information on what conditions DTCs are enabled to test under)
-B148B can be present as a result of a U053B or other communication related DTCs between an Active Safety
Control Module and the Multifunction Energy Storage Capacitor Control Module. Retest and address
communication DTC’s, if present, before addressing the B148B
-Common History DTC List:
- B2B1C
- C0800-03, most common on module B119A Multi-Axis Acceleration Sensor 1
- B101D, Can set in the Long and Short Range Radar's on a partial blockage. It will clear across key cycles but
will cause a "Service Driver's Assist" message.
-Communication DTCs in general but these in particular
- U0499
- U023A/U023B
- U053B/U053C

Diagnostic Event Records:
-Ignore 1BB unless engineering speci es otherwise. This will be noted in SI too.

Diagnostic Event History (DEH):
-Pulling the DEH can provide information that can help with troubleshooting (Information on interpreting can be
found in SI)
-There are some diagnostics that are not indicated by DTC’s but are indicated by the DEH. When they trip, they
can prevent features for the key cycle with no other indication.
Note: When diagnosing Super Cruise Dis-engagements please check for DTCs within the Active Safety Systems.
Do not clear Diagnostic Event History Records at this time, please call TAC for assistance if needed 1-877-4468227.

Unavailable - Across Multiple Drive Cycles:
Super Cruise available icon is not present while driving on controlled access highway at all over multiple key
cycles.
-Verify Diagnostic Codes (HSCAN, LSCAN, MSCAN (Front Object Bus))
-Refer to page # for Diagnostic details
-Verify that Adaptive Cruise is “On”
-Verify the Forward Collision setting is “Alert and Brake”
-Road Not Super Cruise Available - See Super Cruise Freeway Map Site: https://supercruise-map-

viewer.cp.gm.com/
TIP: Scroll Down Page to "Find Super Cruise Freeways Near You" and search by City, State, or ZIP Code.

Unavailable - Intermittently:
Super Cruise available icon is not consistently present while driving on controlled access highway or is turning on
and o during a drive cycle.
-The driver must be centered and stable in the lane to illuminate the Super Cruise available icon.
-Road not Super Cruise capable – see Super Cruise Map Site: https://supercruise-map-viewer.cp.gm.com/

-Di culty tracking lane markings
-Missing or poor lane markings
-Sun glare on road surface
-Heavy Rain/ Puddling / Road spray
-Snow
-Sun shining into front camera at dawn/dusk
-Lock out message for driver attention state (will be present for entire key cycle)
-Exceeding Super Cruise speed in corners
-Exceeding LCC speed capability (85 mph set speed)

Escalations - Attention Based:
Steering wheel goes from solid green to ashing green then to ashing red. Expected reasons for attention based
escalations:
-Sun in Driver Attention System (DAS) camera
-Sun shining into the Driver Attention System (DAS) camera can make it di cult to determine driver attention
state.
-Sun striping on driver's face can make it di cult to determine driver's attention state.
-Squinting can cause the system to incorrectly identify the driver as not being attentive.
-Objects blocking the driver's face can obscure the Driver Attention System (DAS) camera view and cause
escalation.

-Super Cruise will correctly escalate if the driver is looking o road.

Escalations - Other:
Steering wheel goes from solid green directly to ashing red. Expected reasons for escalations are:
-Road not Super Cruise capable – see Super Cruise Map Site: https://supercruise-map-viewer.cp.gm.com/
-Di culty tracking lane markings
-Missing or poor lane markings
-Sun glare on road surface
-Heavy Rain/ Puddling
-Snow
-Sun shining into front camera at dawn/dusk, exiting from under a bridge/overpass
-Vehicle in exit lane (1/2 km before exit)
-Freeway ending (1/2 km before end)
-Freeway split (1/2 km before end)
-Adjacent vehicle in close proximity
-Driving in a tunnel for more than 1 km
-Lanes entering or exiting on both left and right side of the highway
-Areas of construction where roadway deviates from mapped road
-Vehicle entering very tight curve (rare)
-Speci c escalations will cause the vehicle to begin applying brakes, this is intended (poor/loss of lane lines)

Poor Control - Longitudinal:
Poor longitudinal control can be broken into following categories
-False Braking – deceleration when not desired
-Curve speed control
-Super Cruise can reduce/limit vehicle speed to con dently navigate curves. You will get curved road icon
on IPC while in curve speed control if there is no car icon present. (See Picture Below)

-Car in adjacent lane
-Super Cruise may mistakenly think vehicle in adjacent lane is the same lane and decel the car. You will have a
car icon in IPC when decelerating for vehicle.
-Headlights of oncoming vehicles
-Missed Braking – late or no braking when deceleration is desired
-System can have di culty identifying a never before seen stationary vehicle
-Adaptive cruise and Super Cruise

-Cut in / Merging vehicle
-Adaptive cruise and Super Cruise may have di culty with cars merging aggressively or very slowly. Driver
responsible in these situations.
-Tra c around road corners

Poor Control - Lateral:
Poor lateral control means the vehicle was moving side to side. Possible reasons for poor lateral control:
-Di culty tracking lane markings
-Missing or poor lane markings/Signi cant tar stripping on road
-Sun glare on road surface
-Heavy Rain/ Puddling
-Snow
-Sun shining into front camera at dawn/dusk, exiting from under a bridge
-Driving next to exits and entrances
-Lane splits/Freeway splits
-Low speed tra c conditions can result in noticeable control movement
-Construction areas

Super Cruise - Additional Info Needed:
DTC’s:
Location Detail (Hwy details, which lane, direction of travel, passing ramp exit /entrance, freeway split):
Reference Point (Mile marker or city):
Time of day:
Weather Conditions (Sunny/cloudy/rain/snow/ high wind):
Is the issue repeatable:
For Escalation (Solid green to ashing red or ashing green to ashing red):

Version History
Version

Modi ed

4
11/02/2017 – Created on
11/21/2017 – Updated Correction information
12/1/201 – Re-entered to Update Correction information
01/14/2019 – Updated Model Years
01/14/2020 - Updated Model Years

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