Powertrain, generic (extended)

P26E7 Actuator Supply Voltage D Circuit/Open

Check engine lightOn
EmissionsRelevant
Drive cycleRequired
Limp modePossible

Supply D is the fourth switched rail with which a control module powers a group of solenoids or other loads, after A (P0657), B (P2669) and C (P2684). P26E7 reports an open load on it. GM's 2023 and 2024 TCM tables assign the code to high-side output 8 and run the check only while the module shuts down: once the output is off and a low-side output on the same load is switched on, the load should pull the line down. If more than 40 % of battery voltage remains, the module keeps the finding in permanent memory and raises the code once it restarts, Type A. Ford's 2024 summary lists P26E7 as the open-load fault of high side driver 8 in the TR9070 dual-clutch gearbox. Everything fed from that rail is without power, so a substitute gear or limp mode is to be expected.

Likely causes

Broken wire or loose, corroded connector between the module output and the loads on supply D
Open coil in a solenoid powered from this rail
Internal fault in the high-side output of the transmission control module

Symptoms

  • Check engine or transmission warning light on
  • Transmission stays in a substitute gear or limp mode
  • Several solenoid or clutch codes stored at the same time

Repair estimate

DifficultyHardWorkshop job
Parts and labour€100–1,500
Time1–5 h

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

Parts involved

actuator supply dcontrol modulewiring harness

Related codes

P26E8P26E9P2684P2669P0657

References: gsi.ext.gm.com, gsi.ext.gm.com, fordservicecontent.com.