Powertrain, generic (extended)

P27B2 Internal Control Module Transmission Range Control Performance

Check engine lightOn
EmissionsNot relevant
Drive cycleNot required
Limp modePossible

P27B2 is set when the monitoring layer cannot confirm that the gearbox is really in the range the main software intends. In GM's 2024 tables for heavy-duty trucks, the TCM checks actual solenoid and pressure switch states with the pattern expected for the range; if they disagree for a full second, the code is logged, lighting the MIL on the first trip. Ford's 2020–2024 summaries treat it as a non-MIL fault on cars with electronic shifting, recognised in less than 3 s. Ford bulletins tie it to electronic shifter events: SSM 47877 (Navigator 2018/19 and Nautilus 2019, stuck in park after R or D was chosen from remote start without braking), SSM 49642 (Explorer and Aviator built for 2020/21, park release used in the plant) and TSB 25-2362 (2023–2025 Escape and Corsair hybrids, 2025 Maverick hybrid, MIL from SOBDMC software).

Likely causes

Module software (Ford fixes by reprogramming, e.g. TSB 25-2362)
Unusual operating sequence such as selecting a gear after remote start without braking
Solenoid or pressure switch state not matching the commanded range

Symptoms

  • Vehicle stuck in park or will not start
  • Warning lamp or transmission message
  • Range change refused

Repair estimate

DifficultyShop_onlyWorkshop job
Parts and labour€0–1,500
Time0.3–4 h

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

Parts involved

tcm

Related codes

P27B1P27B3P27B4P07E4P0705

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