Powertrain, generic (extended)

P2AB8 Wastegate Position Sensor A Circuit Low

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modePossible

P2AB8 means the wastegate A position signal has fallen below its valid floor, which points to a short to ground, an open signal or reference wire, or a dead sensor. GM's 2019 tables for the 2.7L L3B read the sensor as a percentage of its reference and fail below 5 % in 30 of 38 samples taken every 100 ms; the 2025 tables use below 1 % in 10 of 12. Both run only outside cranking with powertrain relay voltage of at least 11 V and are Type A, so the lamp lights in the first trip. Ford's 2020-23 gasoline summary sets it under 0.50 V after 4 s. Stellantis case S2308000121 traces P2AB8 with P0245 on the Jeep Wrangler to a pinched harness between turbo and intake hose. P2AB9 is the high side, P2ABB bank 2.

Likely causes

Sensor harness pinched or chafed between turbocharger and intake hose (short to ground)
Open reference or signal wire, or pushed-out terminal in the actuator connector
Position sensor inside the electric actuator failed

Symptoms

  • Check engine light from the first trip
  • Reduced power because boost control is restricted
  • May appear together with P0245 when a shared harness section is damaged

Repair estimate

DifficultyMediumDIY possible
Parts and labour€20–800
Time0.5–3 h

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

Parts involved

wastegate position sensor awiring harnessecm

Related codes

P2AB7P2AB9P2ABBP2B81P0245P0641

References: gsi.ext.gm.com, gsi.ext.gm.com, fordservicecontent.com, static.nhtsa.gov.