P2904 on Fiat
Transmission Fluid Temperature Sensor "C" Circuit Low
P2904 on Fiat vehicles indicates transmission fluid temperature sensor "c" circuit low. Au7o has documented this code across 1 Fiat model — most commonly on Uno. This generic powertrain code sets when the Powertrain Control Module (PCM) or Transmission Control Module (TCM) detects that the voltage signal from the "C" transmission fluid temperature (TFT) sensor circuit is lower than the expected/calibrated range. A low circuit reading typically corresponds to an implausibly high fluid temperature indication, signaling a short to ground, a sensor fault, or a wiring problem in that temperature-sensing circuit. Typical repair costs on Fiat range from $350 to $1,200, depending on the specific model and root cause.
Common Causes of P2904
- •Short to ground in the TFT 'C' sensor signal wiring or connector
- •Failed/out-of-range transmission fluid temperature sensor
- •Corroded, damaged, or loose sensor connector pins
- •Damaged wiring harness (chafed or pinched wires) in the transmission circuit
- •Low or contaminated transmission fluid affecting sensor readings
- •Faulty PCM/TCM (less common)
P2904 on Fiat by Model
Fiat Uno(1 issue)
- Dualogic/GSR Automated Manual Transmission Faults and Neutral Drop-Out (Including 2019 Recall)2011-2019
The single-clutch automated manual offered on the Novo Uno (Dualogic on the 1.4 Fire Evo, GSR on the 1.3 Firefly 'Uno Drive') is the model's most expensive weak point. Chronic failure modes documented by Brazilian transmission specialists include worn or mis-calibrated clutch actuators causing slipping and jerky engagement, hydraulic pressure loss from leaks (pump shuts down, codes P0942/P2712), failed gear/clutch position sensors (P0805/P0806, P0715/P0725) and TCU faults that force the transmission into emergency mode or drop it into neutral while driving. It became serious enough that in 2019 Fiat recalled 11,669 vehicles across 8 models — including 916 Uno 1.3 GSR units, model years 2017-2018 (chassis 796635 to 835113) — because the transmission could shift to neutral involuntarily, causing sudden loss of drive.
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View P2904 across all makes →Frequently Asked Questions
What does P2904 mean on Fiat?▼
P2904 stands for "Transmission Fluid Temperature Sensor "C" Circuit Low." This generic powertrain code sets when the Powertrain Control Module (PCM) or Transmission Control Module (TCM) detects that the voltage signal from the "C" transmission fluid temperature (TFT) sensor circuit is lower than the expected/calibrated range. A low circuit reading typically corresponds to an implausibly high fluid temperature indication, signaling a short to ground, a sensor fault, or a wiring problem in that temperature-sensing circuit. On Fiat specifically, this code is documented across 1 model.
What causes P2904 on Fiat vehicles?▼
Common causes on Fiat: Short to ground in the TFT 'C' sensor signal wiring or connector, Failed/out-of-range transmission fluid temperature sensor, Corroded, damaged, or loose sensor connector pins, Damaged wiring harness (chafed or pinched wires) in the transmission circuit, Low or contaminated transmission fluid affecting sensor readings. Specific causes vary by model and year — see the per-model sections below.
How much does it cost to fix P2904 on a Fiat?▼
Repair costs on Fiat range from $350 to $1,200, depending on the specific model and root cause.
Which Fiat models have P2904 documented?▼
Au7o has documented P2904 on 1 Fiat model: Uno.