Powertrain, generic · Transmission

P0974 Shift Solenoid A Control Circuit High

Check engine lightOn
EmissionsRelevant
Drive cycleRequired
Limp modePossible

High-voltage fault in the control circuit of shift solenoid A. What it covers depends on the maker. Ford reserves it for a short to power on SSA, because an open SSA circuit sets P0750. GM six-speeds put both an open and a power short of the mode 2 solenoid here: 1.2 of 1.5 s, MIL only after two trips. The Saab 9-4X 6T70 waits 2 s, Type B, and then blocks 1st gear. GM's Allison 1000 tables of 2016 and 2023 treat it as a pure power short (0.39 ohm or less, 3 samples, 75 or 60 ms) and report opens separately. Saab's Aisin gearbox in the 9-5 (2010) sets it when solenoid valve 2 reads off while commanded on, 100 ms five times, Type A. Ground-side faults are P0973.

Likely causes

Open coil or broken wire where the maker reports opens under the high code (GM six-speed)
Control wire shorted to a supply voltage
Spread or corroded pins at the transmission connector
Faulty driver stage in the control module

Symptoms

  • MIL on, on GM six-speeds only after a second faulty trip
  • First gear locked out, start-off in a higher gear
  • Missing or wrong shifts, possibly 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 awiring harnesstcm

Related codes

P0973P097AP0972P0750P0752

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