From d93039698ccf7c1bfb1ae12a50188eacca1ecfca Mon Sep 17 00:00:00 2001
From: Beartech <233074906+beartech-ca@users.noreply.github.com>
Date: Mon, 29 Jun 2026 18:16:17 -0700
Subject: [PATCH] Add BUICK_LACROSSE_ASCM_19US variant with 37 mph
 minSteerSpeed

US 2019 Buick LaCrosse factory LKA operates only 60-180 km/h. Split it
from BUICK_LACROSSE_ASCM into its own variant so minSteerSpeed can be
raised above the EPS LKA-activation threshold (~12.5 m/s), preventing the
"LKAS Fault: Restart the car to engage" on deceleration. Manual
fingerprint selection only; base LaCrosse platforms unchanged.
---
 opendbc_repo/opendbc/car/gm/interface.py             | 4 +++-
 opendbc_repo/opendbc/car/gm/values.py                | 5 +++++
 opendbc_repo/opendbc/car/torque_data/substitute.toml | 1 +
 3 files changed, 9 insertions(+), 1 deletion(-)

diff --git a/opendbc_repo/opendbc/car/gm/interface.py b/opendbc_repo/opendbc/car/gm/interface.py
index 19f2c515f..d061a9a25 100755
--- a/opendbc_repo/opendbc/car/gm/interface.py
+++ b/opendbc_repo/opendbc/car/gm/interface.py
@@ -422,8 +422,10 @@ class CarInterface(CarInterfaceBase):
       ret.steerActuatorDelay = 0.2
       CarInterfaceBase.configure_torque_tune(candidate, ret.lateralTuning)
 
-    elif candidate in (CAR.BUICK_LACROSSE, CAR.BUICK_LACROSSE_ASCM):
+    elif candidate in (CAR.BUICK_LACROSSE, CAR.BUICK_LACROSSE_ASCM, CAR.BUICK_LACROSSE_ASCM_19US):
       CarInterfaceBase.configure_torque_tune(CAR.BUICK_LACROSSE, ret.lateralTuning)
+      if candidate == CAR.BUICK_LACROSSE_ASCM_19US:
+        ret.minSteerSpeed = 37 * CV.MPH_TO_MS
 
     elif candidate == CAR.CADILLAC_ESCALADE:
       ret.minEnableSpeed = -1.  # engage speed is decided by pcm
diff --git a/opendbc_repo/opendbc/car/gm/values.py b/opendbc_repo/opendbc/car/gm/values.py
index 7aa0a9b96..75cc5c2e0 100644
--- a/opendbc_repo/opendbc/car/gm/values.py
+++ b/opendbc_repo/opendbc/car/gm/values.py
@@ -283,6 +283,10 @@ class CAR(Platforms):
     [GMCarDocs("Buick LaCrosse 2017-19 ASCM Harness")],
     BUICK_LACROSSE.specs,
   )
+  BUICK_LACROSSE_ASCM_19US = GMPlatformConfig(
+    [GMCarDocs("Buick LaCrosse 2019 US ASCM Harness")],
+    BUICK_LACROSSE.specs,
+  )
   BUICK_REGAL = GMASCMPlatformConfig(
     [GMCarDocs("Buick Regal Essence 2018")],
     GMCarSpecs(mass=1714, wheelbase=2.83, steerRatio=14.4, centerToFrontRatio=0.4),
@@ -587,6 +591,7 @@ ASCM_INT = {
   CAR.CADILLAC_ESCALADE_ASCM,
   CAR.CADILLAC_ESCALADE_ESV_2019_ASCM,
   CAR.BUICK_LACROSSE_ASCM,
+  CAR.BUICK_LACROSSE_ASCM_19US,
 }
 
 STEER_THRESHOLD = 1.0
diff --git a/opendbc_repo/opendbc/car/torque_data/substitute.toml b/opendbc_repo/opendbc/car/torque_data/substitute.toml
index cc87cdcc5..6f95b4cba 100644
--- a/opendbc_repo/opendbc/car/torque_data/substitute.toml
+++ b/opendbc_repo/opendbc/car/torque_data/substitute.toml
@@ -66,6 +66,7 @@ legend = ["LAT_ACCEL_FACTOR", "MAX_LAT_ACCEL_MEASURED", "FRICTION"]
 
 "BUICK_LACROSSE" = "CHEVROLET_VOLT"
 "BUICK_LACROSSE_ASCM" = "CHEVROLET_VOLT"
+"BUICK_LACROSSE_ASCM_19US" = "CHEVROLET_VOLT"
 "BUICK_REGAL" = "CHEVROLET_VOLT"
 "CADILLAC_ESCALADE_ASCM" = "CADILLAC_ESCALADE"
 "CADILLAC_ESCALADE_ESV" = "CHEVROLET_VOLT"