Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Circuit/System Verification
- DTC P15F6 is an informational DTC.
- Diagnose all other K20 Engine Control Module DTCs prior to DTC P15F6.
- Verify there are no other K20 Engine Control Module or communication DTCs set.
- If a DTC is set
- If a DTC is not set
- Complete the diagnosis by looking for an intermittent serial data circuit fault. Refer to Scan Tool Does Not Communicate with High Speed GMLAN Device
.
- If an intermittent serial data circuit fault is found
Repair as necessary.
- If an intermittent serial circuit fault is not found
- If an intermittent serial data circuit fault is found
- Clear DTCs and operate the vehicle in the conditions that the customer experienced.
- Verify DTC P15F6 does not set.
- If the DTC sets
Replace K124 Active Safety Control Module
- If the DTC does not set
- If the DTC sets
- All OK.
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.
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