P26A5 code meaning
Engine Coolant Bypass Valve A Position Sensor Circuit Range/Performance
Powertrain system Generic code P26xx codes Check engine light
What P26A5 means
Here the feedback signal is electrically present but sits where a healthy valve should never be. In GM's 2016 Volt table the VICM treats readings between 5 and 30 % or between 70 and 95 % of the reference as invalid; 80 failures in 100 samples at 100 ms give a Type B fault, provided the drive codes P2682/P2683/P26AD/P26AE and P26A6/P26A7 are clear. The same GM document lists a faster 3-of-5 variant for the ELR. On the first-generation Volt (2011) this zone check was still part of P26A9. Subaru's bulletin 09-80-21 blames sensor corrosion for P26A-series codes and fits a redesigned valve. A worn sensor track, a damaged gear between motor and sensor or a mis-seated connector are the usual suspects.
P26A5 at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modeNot expected
- Repair difficultyMedium
- Typical labor0.7 to 4 hours
- Clears after repairAfter a drive cycle
Symptoms of P26A5
- Check engine light after two drives
- Engine runs too cool or warms up slowly
- Fluctuating heater output
Common causes of P26A5
- Most likelyWorn or corroded position sensor track inside the valve
- PossibleDamaged gear or coupling between valve motor and sensor
- PossibleHigh contact resistance at the valve connector
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Coolant bypass valve aPosition sensor
What each part of P26A5 means
| P | Powertrain system: engine, fuel system, ignition, emissions and transmission. |
| 2 | Generic code (second SAE range): it means the same on every make. |
| 6 | Area: computer (engine control module) and output circuits. |
| A5 | The exact fault in that area. |
What to do next
- Note P26A5 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 P26A5
What does P26A5 mean?
P26A5 means "Engine Coolant Bypass Valve A Position Sensor Circuit Range/Performance". Here the feedback signal is electrically present but sits where a healthy valve should never be. It is a generic code, so it means the same on every make.
Is it safe to drive with P26A5?
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 P26A5 fail an emissions test?
Yes, it can. P26A5 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 P26A5 to fix?
Difficulty: medium. A typical repair takes 0.7 to 4 hours of work. This is a job for a workshop.
Will P26A5 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.