Powertrain, generic (extended)

P23E4 EGR C Control Circuit High

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modeNo

P23E4 is the high counterpart: the control circuit of EGR valve C carries a level that is too high. Typical are a drive line touching a battery feed, a connector pin bent onto a supply terminal, or an output stage that no longer pulls its side low. Unlike a ground short, a short to voltage can leave the actuator partly energized, so depending on the design the valve may move unexpectedly or not at all. The equivalents for valves A and B are P0490 and P045D. Which component carries the letter C differs between manufacturers, and none publishes P23E4 with thresholds. Under the CARB rule such output faults have to be detected. The engine usually runs normally, EGR path C is switched off and the warning lamp comes on. Related: P23E1, P23E3.

Likely causes

Drive wire of valve C touching a battery feed
Bent pin in the valve C connector
Engine module output stage not pulling low

Symptoms

  • Warning lamp on
  • Valve C moves unexpectedly or not at all

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

P23E1P23E3P23E2P0490P045D

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