P2493 code meaning
EGR Cooler Bypass Position Sensor Range/Performance (Bank 1)
Powertrain system Generic code P24xx codes Check engine light
What P2493 means
P2493 is a plausibility fault: the bank 1 bypass position signal stays inside its electrical limits, but its value or behaviour does not fit the commanded flap position or the learned end stops. GM names the code in preliminary bulletin PI1449 for the 2015 Silverado and Sierra with the LML Duramax, where it showed up together with P2495, P24C4 and P06A3. The fix there was a complete new bypass valve, since the sensor sits in the valve and must not be taken apart. Range errors often come from a worn sensor track, a shaft that turns without the sensor following, or deposits that shift the end positions. The pure circuit faults are P2492, P2494 and P2495; bank 2 reports P2498.
P2493 at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modeNot expected
- Repair difficultyMedium
- Typical labor1 to 4 hours
- Clears after repairAfter a drive cycle
Symptoms of P2493
- Check engine light on, often with further bypass codes
- Bypass position in the live data does not match the command
Common causes of P2493
- Most likelyWorn or defective bypass valve with integrated sensor
- PossibleDeposits shifting the learned end positions
- Less likelyUnstable 5 V reference shared with other sensors
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
EGR cooler bypass position sensor b1
What each part of P2493 means
| P | Powertrain system: engine, fuel system, ignition, emissions and transmission. |
| 2 | Generic code (second SAE range): it means the same on every make. |
| 4 | Area: auxiliary emission controls (catalytic converter, EGR, EVAP). |
| 93 | The exact fault in that area. |
What to do next
- Note P2493 and any other codes stored with it: several codes together often point to one cause.
- Check for loose connectors and damaged wiring around the parts the code names.
- Check open recalls for your car: some faults are fixed for free by the dealer. Enter your VIN.
- Clear the code only after the repair. If it comes back, the fault is still there.
Buying a used car? Scan it for stored codes before you pay. A recently cleared memory can hide a problem.
Questions about P2493
What does P2493 mean?
P2493 means "EGR Cooler Bypass Position Sensor Range/Performance (Bank 1)". P2493 is a plausibility fault: the bank 1 bypass position signal stays inside its electrical limits, but its value or behaviour does not fit the commanded flap position or the learned end stops. It is a generic code, so it means the same on every make.
Is it safe to drive with P2493?
Usually yes, for a short time, if the check engine light is steady and the car drives normally. If the light flashes or the car runs badly, stop and have it checked.
Will P2493 fail an emissions test?
Yes, it can. P2493 is emissions-related, so most inspection programs fail a car while it is stored or while the check engine light is on.
How hard is P2493 to fix?
Difficulty: medium. A typical repair takes 1 to 4 hours of work. This is a job for a workshop.
Will P2493 clear itself after the repair?
After the repair the car has to complete a drive cycle (a mix of city and highway driving) before the test runs again. Until then the readiness monitor shows "not ready", which can fail an inspection.