Active Exhaust System Status
This code indicates that the active exhaust system is experiencing an issue.
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 truck's computer is tracking the active exhaust system, which helps reduce emissions. When it sees a problem, it flags this code to tell you there's an issue that needs looking into.
What the computer is actually seeing
The computer monitors inputs from exhaust sensors, and if readings fall outside the normal operating range, it triggers this fault code. Typical signals could be voltages from sensor 1 in the range of 0.1V to 4.5V indicating the system's status.
What a healthy reading looks like
Expected exhaust system pressure values should be around 5 to 12 psi under normal operating conditions. Any significant deviations from this may trigger a fault.
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. Check the wiring and connectors to the exhaust pressure sensor for damage or corrosion, ensuring a good connection. This is the easiest and cheapest step.
- 22. Measure the voltage at the exhaust pressure sensor. It should be between 0.1V and 4.5V. If it's out of this range, replace the sensor.
- 33. Inspect the exhaust system for blockages or restrictions that could affect pressure readings. Clear any obstructions found.
- 44. If the sensor and wiring check out, scan for other related codes that may give additional context about the issue. Check for SPN 4364 and SPN 160 as they often appear with this code.
- 55. If other codes are present, address those issues accordingly and retest the system.
Common causes
- Faulty exhaust pressure sensor
- Blockage in the exhaust system
- Wiring issues or bad connectors
- Faulty control module for active exhaust system
Typical repair cost
$$
Related codes
Frequently asked questions
Is it safe to drive with this code?
It's not recommended to drive for long with this code, as it could impact emissions and cause further issues.
Will this code come back after repairs?
If the root cause is fixed properly, the code should not return.
Why does this code appear with other SPN codes?
This code can pair with SPN codes that relate to exhaust or emissions systems, indicating multiple related issues.
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