Ignition Switch Circuit Failure
The ignition switch circuit has a failure, affecting vehicle start-up.
Heads up: this code wasn't in our hand-written library yet, so DiagCoach AI built this page on the fly. Double-check critical specs against service info before condemning parts.
What it means (plain English)
The ignition switch is sending a signal that doesn’t match what the computer expects, which could prevent the vehicle from starting or operating correctly.
What the computer is actually seeing
The computer sees an unexpected voltage level from the ignition switch circuit. It generally expects about 12V when the key is in the 'On' position and around 0V when the switch is in 'Off'.
What a healthy reading looks like
12V in 'On', 0V in 'Off'.
Guided diagnostic — the DiagCoach way
Don't just throw parts at it. Walk through these in order — each step tells you whether to keep going or stop and fix what you found.
- 11. Inspect the ignition switch for physical damage or wear.
- 22. Check wiring and connectors for any signs of corrosion or loose connections.
- 33. Using a multimeter, check the voltage at the ignition switch with the key in 'On' position; it should read around 12V.
- 44. If voltage is correct, check continuity from the ignition switch to the PCM.
- 55. If there’s no continuity, repair or replace faulty wiring.
- 66. If all checks out but the code persists, consider replacing the ignition switch.
Common causes
- Faulty ignition switch
- Wiring issues between the ignition switch and the control module
- Corroded or loose connectors at the ignition switch or PCM
- Faulty powertrain control module (PCM)
Typical repair cost
$$$
Related codes
Frequently asked questions
Is it safe to drive with this code?
It's not safe to drive if the ignition switch isn't functioning properly, as it can cause the vehicle to stall.
Will this code come back after I clear it?
If the underlying issue isn't fixed, yes, the code will likely return.
Why does this code pair with B161A?
Both codes are related to ignition switch issues, but they may indicate different faults within the circuit.
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