P045CEGR B Control Circuit Low
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Can trigger limp mode
- Needs a drive cycle to confirm a fix
- How the car detects it
- Exhaust gas recirculation (EGR) routes part of the exhaust back into the intake to lower combustion temperature and NOx. EGR B is a second EGR valve next to valve A – on diesels with two EGR circuits the low-pressure valve, which takes exhaust after the particulate filter and feeds it in before the turbo compressor. GM's diesels of 2016–18 and FCA's 2.2-litre diesel in the Jeep Wrangler use it. P045C means the drive circuit of valve B is shorted to ground (for valve A, P0489, GM uses 0.5 Ω or less with the driver off, MIL after two trips). The driver is switched off for protection and the valve stays in its rest position. GM lists this code among those that switch off the low-pressure EGR position control, but publishes no thresholds for it; the description follows the comparable valve A checks and CARB, which requires output circuits to be monitored.
- What you may notice
- Check engine light on
- Low-pressure EGR switched off, possibly higher NOx
- Usually no change in driving
- Likely causes
- LikelyControl wire chafed against ground (engine, exhaust)
- PossibleActuator motor winding shorted
- PossibleWater or corrosion in the connector
- RareDriver in the engine module
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Medium · Usually a job for a workshop.Typical cost: €80 – €700
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.