Powertrain, generic

P0E5D DC/DC Converter Enable Circuit Intermittent/Erratic

Check engine lightOn
EmissionsNot relevant
Drive cycleRequired
Limp modePossible

P0E5D adds the intermittent case to the DC/DC converter enable codes P0A11 (open), P0A12 (low) and P0A13 (high). Through the enable line a hybrid or body controller switches the converter on and off; if that line flickers, the converter keeps stopping and restarting. Converter data sheets show how simple the input often is: on Poclain's 48 V unit the converter runs while the enable pin is tied to input positive or left floating and shuts off when it is pulled to input negative, so a poor ground or chafed wire can cycle it. No manufacturer documents P0E5D publicly. Ford's hybrid summaries use only P0A11 and attach several internal boost converter faults to it. CARB requires output components to be checked for circuit faults. The driver may see the 12 V voltage dip or a battery warning that comes and goes.

Likely causes

Loose or corroded terminal on the enable line
Poor ground reference between controller and converter
Chafed enable wire touching ground intermittently
Output stage in the commanding controller faulty

Symptoms

  • 12 V battery warning that comes and goes
  • Fluctuating system voltage, flickering lights
  • Hybrid warning, possibly reduced power

Repair estimate

DifficultyHardWorkshop job
Parts and labour€60–1,500
Time0.5–4 h

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

Parts involved

dcdc converter enable circuitwiring harnesshybrid control module

Related codes

P0A11P0A12P0A13P0A08

References: law.cornell.edu, poclain.com, fordservicecontent.com.