Powertrain, generic · Transmission

P0980 Shift Solenoid C Control Circuit High

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modePossible

High-voltage fault in the control circuit of shift solenoid C, meaning a short to supply. GM documents it for the Allison 1000 six-speed: the 2007 table wants four consecutive power-short samples (100 ms, Type A) and skips the check in reverse trim, 5th and 6th gear; later tables (2016, 2018) look for 0.39 ohm or less to a supply over three counts within 75 ms, and from 2022 within 60 ms, MIL after one trip. Ford uses it for SSC short to power in all its listed gearboxes, with P0760 for an open. Neither GM's 6L/6T six-speeds nor Saab's documented gearboxes use P0980. The ground counterpart is P0979, the open code for the Allison is P097C.

Likely causes

Solenoid C control wire shorted to a supply voltage
Shorted turns in solenoid C lowering its resistance
Adjacent pins bridged by fluid or debris in the connector
Faulty driver stage in the control module

Symptoms

  • MIL on after the first faulty trip
  • Solenoid C stuck energized, wrong gear or default gear
  • Harsh shifts

Repair estimate

DifficultyHardWorkshop job
Parts and labour€100–1,800
Time1–5 h

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

Parts involved

shift solenoid cwiring harnesstcm

Related codes

P0979P097CP0978P0760P0762

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