P0740 on Mazda
Torque Converter Clutch Circuit Malfunction
P0740 on Mazda vehicles indicates torque converter clutch circuit malfunction. Au7o has documented this code across 2 Mazda models — most commonly on CX-3, CX-50. This code indicates a malfunction in the torque converter clutch (TCC) circuit of an automatic transmission. The torque converter clutch mechanically locks the engine to the transmission at cruising speed to improve fuel economy and reduce slippage, and it is engaged by a solenoid controlled by the transmission computer. The code sets when the computer detects an electrical problem with the clutch circuit or sees that the clutch is not engaging or holding as expected. Common signs include slipping, shuddering, poor fuel economy, or stalling when coming to a stop. Typical repair costs on Mazda range from $150 to $1,800, depending on the specific model and root cause.
Common Causes of P0740
- •Faulty torque converter clutch (TCC) solenoid
- •Low or contaminated transmission fluid
- •Wiring or connector fault in the TCC circuit
- •Worn or failing torque converter
- •Valve body wear or sticking valves
- •Internal transmission electrical short
- •Faulty transmission control module
P0740 on Mazda by Model
Mazda CX-3(1 issue)
- Automatic Transmission Shudder2016-2021
The 6-speed automatic transmission in the CX-3 develops a shudder or vibration during light-throttle acceleration at low to moderate speeds (20-45 mph). The torque converter lockup clutch is the typical culprit, with worn friction material causing slip-stick behavior. A transmission fluid change can temporarily resolve the issue, but severe cases require torque converter replacement.
Mazda CX-50(1 issue)
- Transmission Hesitation on Acceleration2023-2025
The 6-speed automatic transmission in the CX-50 exhibits hesitation and delayed shifts when accelerating from a stop or during passing maneuvers. The torque converter lockup strategy and shift programming prioritize fuel economy over responsiveness, causing a noticeable lag. Some owners report improvement after TCM recalibration.
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View P0740 across all makes →Frequently Asked Questions
What does P0740 mean on Mazda?▼
P0740 stands for "Torque Converter Clutch Circuit Malfunction." This code indicates a malfunction in the torque converter clutch (TCC) circuit of an automatic transmission. The torque converter clutch mechanically locks the engine to the transmission at cruising speed to improve fuel economy and reduce slippage, and it is engaged by a solenoid controlled by the transmission computer. The code sets when the computer detects an electrical problem with the clutch circuit or sees that the clutch is not engaging or holding as expected. Common signs include slipping, shuddering, poor fuel economy, or stalling when coming to a stop. On Mazda specifically, this code is documented across 2 models.
What causes P0740 on Mazda vehicles?▼
Common causes on Mazda: Faulty torque converter clutch (TCC) solenoid, Low or contaminated transmission fluid, Wiring or connector fault in the TCC circuit, Worn or failing torque converter, Valve body wear or sticking valves. Specific causes vary by model and year — see the per-model sections below.
How much does it cost to fix P0740 on a Mazda?▼
Repair costs on Mazda range from $150 to $1,800, depending on the specific model and root cause.
Which Mazda models have P0740 documented?▼
Au7o has documented P0740 on 2 Mazda models: CX-3, CX-50.