C140F on Jeep
Transfer Case Range Position Sensor Erratic Performance
C140F on Jeep vehicles indicates transfer case range position sensor erratic performance. Au7o has documented this code across 1 Jeep model — most commonly on Grand Cherokee. A Chrysler/Dodge/Jeep (FCA) chassis code set by the Final Drive Control Module (FDCM), which monitors the transfer case range position sensor for erratic-performance failures. The transfer case shift actuator reports its position back as an analog/encoder signal; when that signal jumps around or falls outside a valid range, the module cannot determine what range the transfer case is in and sets C140F. Drivers typically see a "Service 4WD" message or 4WD light, and the transfer case may refuse to shift between 4WD High, 4WD Low, and Neutral. It is strongly associated with 2005-2010 Jeep Grand Cherokee and Commander and with Recall N23 — factory instructions call for clearing the code (up to three times) and applying the correct software update after N23 before replacing hardware. It may set together with C1405 (range position sensor circuit high) when the actuator has failed. Typical repair costs on Jeep range from $200 to $2,500, depending on the specific model and root cause.
Common Causes of C140F
- •Corroded or water-intruded connector at the transfer case shift actuator/motor
- •Faulty transfer case range position sensor/encoder inside the actuator assembly
- •Damaged or chafed wiring between the actuator and the FDCM
- •Loose or corroded FDCM connector
- •Outdated FDCM software — code commonly sets after Recall N23 and requires the factory flash/clear procedure
- •Failed transfer case shift motor/actuator assembly
C140F on Jeep by Model
Jeep Grand Cherokee(1 issue)
- Transfer Case Actuator Motor Failure Triggering 'Service 4WD' and Loss of Low Range2011-2021
Grand Cherokees with the two-speed Quadra-Trac II / Quadra-Drive II transfer cases throw a 'Service 4WD System' message when the transfer-case shift actuator motor (or the transfer-case control module) fails, leaving the vehicle unable to engage Low range or Neutral and sometimes producing a grinding noise. Owners and shops report it is difficult to diagnose: replacing the actuator motor does not always fix it, and some vehicles ultimately need a transfer case. Codes such as C140F are associated with the actuator failure. It is a high-demand complaint because the warning is alarming and the off-road/low-range function is lost.
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What does C140F mean on Jeep?▼
C140F stands for "Transfer Case Range Position Sensor Erratic Performance." A Chrysler/Dodge/Jeep (FCA) chassis code set by the Final Drive Control Module (FDCM), which monitors the transfer case range position sensor for erratic-performance failures. The transfer case shift actuator reports its position back as an analog/encoder signal; when that signal jumps around or falls outside a valid range, the module cannot determine what range the transfer case is in and sets C140F. Drivers typically see a "Service 4WD" message or 4WD light, and the transfer case may refuse to shift between 4WD High, 4WD Low, and Neutral. It is strongly associated with 2005-2010 Jeep Grand Cherokee and Commander and with Recall N23 — factory instructions call for clearing the code (up to three times) and applying the correct software update after N23 before replacing hardware. It may set together with C1405 (range position sensor circuit high) when the actuator has failed. On Jeep specifically, this code is documented across 1 model.
What causes C140F on Jeep vehicles?▼
Common causes on Jeep: Corroded or water-intruded connector at the transfer case shift actuator/motor, Faulty transfer case range position sensor/encoder inside the actuator assembly, Damaged or chafed wiring between the actuator and the FDCM, Loose or corroded FDCM connector, Outdated FDCM software — code commonly sets after Recall N23 and requires the factory flash/clear procedure. Specific causes vary by model and year — see the per-model sections below.
How much does it cost to fix C140F on a Jeep?▼
Repair costs on Jeep range from $200 to $2,500, depending on the specific model and root cause.
Which Jeep models have C140F documented?▼
Au7o has documented C140F on 1 Jeep model: Grand Cherokee.