P20E5 code meaning
Exhaust Gas Temperature Sensor 1/2 Correlation (Bank 2)
Powertrain system Generic code P20xx codes Check engine light
What P20E5 means
P20E5 is the bank 2 counterpart of P20E2: on engines with a separate exhaust and aftertreatment path per cylinder bank, sensors 1 and 2 of the second bank disagree after the system has cooled down. No manufacturer documents this exact code publicly; the GM tables that use P20E2 cover single-path diesels. The method is known from Cummins' patent US7771113: once the exhaust has cooled, the thermistors ahead of and behind the oxidation catalyst are checked against each other and an offset sensor is identified, even when its reading is still within range. CARB requires rationality monitoring of every temperature sensor used by an emission strategy. Bank 2 circuit or range faults use P0548, P2082 or P2034. The driver sees the MIL; regeneration of the bank 2 filter may be limited.
P20E5 at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modeNot expected
- Repair difficultyMedium, DIY possible
- Typical labor0.5 to 3 hours
- Clears after repairAfter a drive cycle
Symptoms of P20E5
- Malfunction indicator lamp on
- Bank 2 sensors show different values on a cold engine
Common causes of P20E5
- Most likelyBank 2 sensor 1 or 2 reading offset
- PossibleContact resistance in a bank 2 sensor connector
- Less likelySensor connectors swapped between banks after a repair
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Exhaust gas temperature sensorWiring harness
What each part of P20E5 means
| P | Powertrain system: engine, fuel system, ignition, emissions and transmission. |
| 2 | Generic code (second SAE range): it means the same on every make. |
| 0 | Area: fuel and air metering and auxiliary emission controls. |
| E5 | The exact fault in that area. |
What to do next
- Note P20E5 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 P20E5
What does P20E5 mean?
P20E5 means "Exhaust Gas Temperature Sensor 1/2 Correlation (Bank 2)". P20E5 is the bank 2 counterpart of P20E2: on engines with a separate exhaust and aftertreatment path per cylinder bank, sensors 1 and 2 of the second bank disagree after the system has cooled down. It is a generic code, so it means the same on every make.
Is it safe to drive with P20E5?
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 P20E5 fail an emissions test?
Yes, it can. P20E5 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 P20E5 to fix?
Difficulty: medium. A typical repair takes 0.5 to 3 hours of work. A careful DIY repair is possible with basic tools and a scanner.
Will P20E5 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.