Powertrain, generic · Transmission

P0976 Shift Solenoid B Control Circuit Low

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modePossible

Low-voltage fault, normally a ground short, in the control circuit of shift solenoid B. On GM six-speeds SS B is the mode 3 multiplex valve; the 2016 table sets P0976 after 1.2 of 1.5 s without lighting the MIL, while the Saab 9-4X 6T70 version needs 2 s, is Type B and raises line pressure. Ford uses it for SSB short to ground, with P0755 for an open; on the 2023 Super Duty diesel SSB is fed by solenoid supply TSPC2, so a P2669 supply fault disables this check. GM's Allison 1000 merges ground short and open into it in 2016, but from 2022 reports opens as P097B and keeps P0976 for ground faults found by an intrusive test (120 ms, MIL after one trip). High side is P0977.

Likely causes

Solenoid B control wire shorted to ground or housing
Internal short in solenoid B or its valve body assembly
Moisture or debris bridging pins at the connector
Faulty driver in the transmission control module

Symptoms

  • Warning light or stored code, on some GM six-speeds without MIL
  • Firm shifts due to raised line pressure
  • Gears missing or limp mode

Repair estimate

DifficultyHardWorkshop job
Parts and labour€100–1,600
Time1–5 h

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

Parts involved

shift solenoid bwiring harnesstcm

Related codes

P0977P097BP0975P0755P2669

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