Powertrain, generic (extended)

P2669 Actuator Supply Voltage B Circuit/Open

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modePossible

Many transmission controllers feed their solenoids through internal high-side switches, called actuator supply A and B. Ford's 6R140 splits its Transmission Solenoid Power Control into two wires: TSPC-A powers shift solenoids A, C and E (fault P0657), TSPC-B powers SSB, SSD, TCC and line pressure control (P2669). Because both share one internal switch, any fault switches off all seven solenoids, leaving park, reverse, neutral and 5th gear with full line pressure; Ford lists P2669 with MIL. In GM's 16OBDG08 tables for Silverado/Sierra the TCM flags an open supply 2 when several solenoids on it read open at once while the supply line stays high; GM's 2023 TCM test checks at power-down and logs it as Type A. P2670 and P2671 cover low and high faults.

Likely causes

Open supply wire or connector between module and transmission bulkhead
Damaged internal transmission harness or lead frame
High-side switch inside the controller failed

Symptoms

  • Transmission stuck in a fixed gear (failsafe)
  • Harsh engagements due to maximum line pressure
  • MIL or transmission warning on

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 bcontrol modulewiring harness

Related codes

P2670P2671P0657P2684

References: newtonnet.co.uk, fordservicecontent.com, gsi.ext.gm.com, gsi.ext.gm.com.