Circuit/System Testing

WARNING: This page is about a different car, the 2019 Buick Cascada, 2018 Buick Cascada, and 2017 Buick Cascada. However, it is still accessible from the selected car via links, so may be relevant.

Ignition OFF, exterior lamps OFF, disconnect the harness connector at the appropriate E13 Headlamp Assembly. It may take up to 2 min for all vehicle systems to power down.
Test for less than 10 Ω between the ground circuit terminal 8 and ground.
- If 10 Ω or greater
1. Ignition OFF.
2. Test for less than 2 Ω in the ground circuit end to end.
  - If 2 Ω or greater, repair the open/high resistance in the circuit.
  - If less than 2 Ω, repair the open/high resistance in the ground connection.
- Go to next step: If less than 10 Ω
Ignition ON.
Verify a test lamp illuminates between the B+ circuit terminals 6 and ground.
- If the test lamp does not illuminate
1. Ignition OFF, disconnect the X5 harness connector at the X50A Fuse Block - Underhood.
2. Test for infinite resistance between the B+ circuit and ground.
  - If less than infinite resistance, repair the short to ground on the circuit.
  - Go to next step: If infinite resistance
3. Test for less than 2 Ω in the control circuit end to end.
  - If 2 Ω or greater, repair the open/high resistance in the circuit.
  - If less than 2 Ω, replace the X50A Fuse Block - Underhood.
- Go to next step: If the test lamp illuminates
Ignition OFF, replace the E13 Headlamp Assembly.
Ignition ON, verify DTC B1495 is not set.
- If DTC B1495 is set
  Replace the K26 Headlamp Control Module.
- Go to next step: If DTC B1495 does not set
All OK.