Powertrain, generic (extended)

P23E3 EGR C Control Circuit Low

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modeNo

P23E3 says the control circuit of EGR valve C reads low. On motor or solenoid driven EGR valves this mostly means one of the drive lines has a short to ground, so the output stage would draw excessive current or sees a level it cannot produce by itself. The module then switches the driver off to protect it, and the valve falls back to its spring position, usually closed. For valves A and B the corresponding codes are P0489 and P045C; GM's 2018 diesel tables list both among the faults that request shut-off of the respective EGR position control. No manufacturer documents P23E3 publicly, and no thresholds for valve C are published. CARB requires EGR output circuits to be monitored. Expect higher NOx with little change in driving, plus the warning lamp. High fault: P23E4.

Likely causes

Drive wire of valve C shorted to ground
Internal short in the valve C motor or coil
Faulty output stage in the engine module

Symptoms

  • Warning lamp, little change in driving
  • EGR path C switched off

Repair estimate

DifficultyMediumDIY possible
Parts and labour€40–700
Time0.5–2.5 h

Typical range across vehicles; the real cost depends on what the testing finds.

Parts involved

egr valve c

Related codes

P23E1P23E4P23E2P0489P045C

References: gsi.ext.gm.com, law.cornell.edu.