Powertrain, generic · Hybrid propulsion

P0CED Hybrid/EV Electronics Coolant Pump A Enable Circuit

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modePossible

Some electronics coolant pumps receive two signals: a speed command and a separate enable wire that switches the pump on. P0CED concerns that enable wire. In GM's 2011 Volt (11OBDG01) any open or short on it sets the code after 16 of 20 samples at 250 ms with more than 9 V supply, Type B, two trips. Later GM controllers split the short cases into their own codes and keep P0CED for an open: the HPC2 tables 16OBDG02 and 19OBDG02 fail it when, with enable commanded on, the line rests between 1.14 V and 2.81 V, a level that points to a floating wire. The speed command line itself is P0CE9 to P0CEC. Without enable the pump stays off even though its command looks normal, so electronics temperatures climb and power may be reduced.

Likely causes

Broken enable wire or terminal pushed out of the connector
Enable wire shorted to ground or voltage (codes it on older GM controllers)
Defective enable input inside the pump
Faulty enable driver in the control module

Symptoms

  • Malfunction indicator lamp on
  • Electronics coolant pump remains off
  • Reduced power or charging rate when electronics get warm

Repair estimate

DifficultyMediumWorkshop job
Parts and labour€50–650
Time0.5–3 h

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

Parts involved

hybrid electronics coolant pump awiring harnesshybrid control module

Related codes

P0CE9P0CEAP0CEBP0CECP2E45

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