01 B1075 – Climate Control System Fault: Temperature Regulatio… • 02 Engine Remapping: What It Is, How It Works, and the Pros an… • 03 Porsche vs. Mercedes vs. BMW vs. Audi: Which Brand Will Las… • 04 This Is How Mercedes Magic Body Control Scans The Road • 05 5 Things You Should Know About Oxygen Sensors in Cars • 06 P0034 Turbo charger bypass valve control circuit low • 07 End of an Era: Subaru Legacy Announces Farewell After 36 Ye… • 08 The Top 10 Engine Sensors Every Car Owner Should Know • 09 Adapting to Autonomous Transmissions: How Self-Shifting Car… • 10 Why is your car shaking when you brake at high speeds? •

DTC codes / Kia codes / P1655

P1655 · KiaUnused Power Stage 'B'

P1655 on Kia vehicles indicates that the engine control module (ECM) has detected an unused power stage 'B' output circuit, meaning the ECM is not receiving the expected feedback from a specific actuator or relay circuit that is not used on this application. The ECM sets this code when it sees an open, short, or unexpected voltage on a power stage output that is not configured for the vehicle's build.

SystemPowertrain
Code typeKia specific
SeverityLow
Fix difficultyIntermediate
AreaComputer and output circuits

Symptoms you may notice

  • Often no symptoms besides the warning light
  • Possible intermittent rough running or stalling if the circuit is related to a fuel or ignition component
  • Reduced engine performance or limp mode in some cases
  • Electrical accessories may not function if the power stage controls a relay
  • Intermittent no-start condition if the circuit affects the starter or fuel pump
  • No noticeable change in driveability in most instances

Common causes, most likely first

  1. Faulty or corroded wiring harness connector at the power stage output
  2. Open or shorted wire in the power stage 'B' circuit
  3. Failed relay or actuator that the power stage controls
  4. ECM internal fault causing false detection
  5. Water intrusion or corrosion in the underhood fuse box
  6. Aftermarket accessories improperly wired into the circuit

How to diagnose and fix it

  1. Connect a scan tool and verify P1655 is current, then check for related codes and freeze frame data
  2. Inspect the wiring harness and connectors for the power stage 'B' circuit for damage, corrosion, or loose pins
  3. Test the relay or actuator controlled by the power stage 'B' for proper resistance and operation
  4. Check for voltage drops and continuity on the power stage 'B' circuit from the ECM to the component
  5. Inspect the underhood fuse box for water intrusion or corrosion and repair as needed
  6. If all external circuits and components test good, suspect an internal ECM fault and perform a substitution test with a known-good ECM
  7. Clear codes and verify the repair with a test drive and recheck

What P1655 really means on Kia

  • P1655 is often set by a loose or corroded connector that causes an intermittent open circuit, not by a failed component.
  • On many Kia models, this code is stored in the ECM but does not illuminate the check engine light until the fault occurs multiple times.
  • Aftermarket alarm or remote start installations frequently tap into power stage circuits and can trigger this code.
  • A weak battery or poor ground connection can cause the ECM to misread power stage feedback and set P1655.
  • Do not replace the ECM based solely on this code; always verify the circuit and component first.

Can I keep driving with P1655?

The vehicle is generally safe to drive with P1655 if no driveability symptoms are present, but avoid towing heavy loads or aggressive driving until the fault is diagnosed. If the engine runs rough or stalls, have it inspected promptly.

Tools that help

Tools we recommend are in the Auto Veteran shop on Amazon. As an Amazon Associate we earn from qualifying purchases.

Guidance is general and written for Kia vehicles. Exact tests and values vary by model, so confirm the fault before replacing parts.

Running on fumes Free guides aren't free to make. Top up the tank. Any amount, one time. Fuel the Garage