P0740: Torque Converter Clutch Circuit Malfunction
Key takeaways
- P0740 means the transmission computer sees an electrical problem in the circuit that controls the torque converter lockup clutch.
- Most cars drive normally with it, but the converter never locks, so highway RPM, fuel use and fluid temperature go up.
- Wiring, connectors and the lockup solenoid are the usual answers; the torque converter itself is rarely the cause of this code.
- Chrysler, Dodge, Jeep and Ram bulletins naming P0740 are mostly computer software updates and transmission replacement procedures.
- Most fixes run about $100 to $1,500, from a software update to a replaced and programmed transmission computer.
What P0740 means
The computer can’t properly control the clutch that locks your torque converter. At cruising speed, a clutch inside the converter locks the engine straight to the transmission so the converter stops slipping. A solenoid in the transmission applies that clutch when the transmission computer tells it to. The computer watches the solenoid’s electrical circuit, and when the voltage or current it sees doesn’t match what it commanded (open, shorted or out of range), it stores P0740, “Torque Converter Clutch Circuit Malfunction.” Some scanners show it as “TCC Circuit” or “Lockup Solenoid Circuit.”
Is it safe to drive?
Yes, in most cases, while you arrange a repair. Most transmissions simply stop locking the converter when this code sets. The car still drives, but RPM sits a few hundred higher on the highway, fuel economy drops and the fluid runs hotter. The symptom that changes the answer: if the transmission slips, flares between gears, shifts harshly, gets stuck in one gear (limp mode), or the fluid smells burnt, keep trips short and get it in quickly. Heat is what destroys transmissions, and a wiring repair is much cheaper than a rebuild.
Causes, ranked
| Cause | How you confirm it | Typical cost (US independent shop, 2026) |
|---|---|---|
| Damaged wiring or a corroded connector at the transmission | Visual check, wiggle test, circuit resistance from the computer to the solenoid | $100–$250 |
| Failed torque converter clutch (lockup) solenoid | Solenoid resistance out of spec; commanding it on with a scan tool does nothing | $300–$1,200 (inside the pan on some units, part of a solenoid pack or valve body on others) |
| Transmission or engine computer software | A bulletin covers your make, model and year | $100–$200 |
| Low or badly worn fluid adding to the fault | Level and condition check | $150–$300 for a fluid service |
| Failed transmission (or engine) computer driver | Wiring and solenoid test good, the computer’s output doesn’t switch | $500–$1,500 including programming |
A torque converter ($1,000–$2,500) is rarely the answer to P0740 alone. It comes up when P0741 is also set and the electrical side tests good.
What to check first
- Check the fluid. Level and condition, using your car’s check procedure (many need the engine running and the fluid hot). If you see red fluid under the car, fix the leak too.
- Look at the wiring and connector at the transmission case for chafing, oil soaking or green corrosion. Unplug, inspect, plug back in firmly.
- Look for a bulletin. In the bulletins that name P0740, the pattern is Chrysler, Dodge, Jeep and Ram: computer software updates on 2019 Ram 2500 and 3500 trucks, plus procedures for replacing the transmission or torque converter on 62TE-equipped vehicles such as the Promaster.
- Test the solenoid. Resistance and an activation test with a scan tool. This separates a bad solenoid from a bad wire in minutes.
- Clear it and drive only after a repair. If it comes straight back with the wiring and solenoid good, the computer or its software is next.
NHTSA data shows 119 complaints filed with NHTSA mention P0740, most of them older Hondas: the Honda Odyssey with 50 (mostly 2000–2004 models), the Civic with 20 and the Accord with 18. Those are owner reports, not confirmed causes.
What it costs
The cheap outcome is a wiring or connector repair or a software update, about $100–$250. The common outcome is a lockup solenoid, $300–$1,200 depending on whether it bolts on alone or comes as part of a solenoid pack. The expensive outcome is a transmission computer at $500–$1,500 including programming. Testing the circuit before buying parts is what keeps you at the low end. If the car jerks while driving as well, tell the shop.
Related codes
P0740 often shows up with P0741 (clutch not locking), P0742 (stuck on) or P0744 (intermittent). If more than one solenoid code is stored at once, look hard at the shared connector and power supply. On some cars the engine computer also stores P0700, which just means “the transmission computer has a code.”
What owners report to NHTSA
119 complaints filed with NHTSA mention P0740, 21 of them since 2015, across 22 different models. The component owners most often filed it under: power train:automatic transmission.
Most-reported models
| Vehicle | Complaints | Model years reported |
|---|---|---|
| HONDA ODYSSEY | 50 | 2000, 2001, 2002, 2003, 2004 |
| HONDA CIVIC | 20 | 1999, 2001 |
| HONDA ACCORD | 18 | 1998, 1999, 2000, 2001, 2002 |
| ACURA TL | 5 | 2000, 2003 |
| HONDA PILOT | 4 | 2003, 2004 |
| DODGE GRAND CARAVAN | 3 | 2011, 2015 |
Manufacturer service bulletins that name P0740
78 technical service bulletins and manufacturer communications filed with NHTSA mention P0740, from 11 makes. A bulletin means the manufacturer has documented a known cause or a fix procedure for that model. Examples:
- FCA FCA, bulletin 10193950: Transmission Kit with Torque Converter 1. All Promaster (VF) 3.6L/62TE equipped vehicles. If the transmission bracket to the transmission case fasteners are removed during servicing, the fasteners (Part Number 06511385A$…
- RAM PROMASTER (2015, 2016, 2017, 2018), bulletin 10220631: Remanufactured Transmission Assembly 1. All Promaster (VF) 3.6L/62TE equipped vehicles: a) If the transmission bracket to the transmission case fasteners are removed during servicing, the fasteners (Part Number 06511385A…
- ALFA ROMEO 4C (2018, 2017, 2019, 2020), bulletin 10221097: Transmission Kit with Torque Converter 1. All Promaster (VF) 3.6L/62TE equipped vehicles. If the transmission bracket to the transmission case fasteners are removed during servicing, the fasteners (Part Number 06511385A$…
- CHRYSLER 200 (2010, 2011, 2012, 2013), bulletin 10221097: Transmission Kit with Torque Converter 1. All Promaster (VF) 3.6L/62TE equipped vehicles. If the transmission bracket to the transmission case fasteners are removed during servicing, the fasteners (Part Number 06511385A$…
- DODGE AVENGER (2007, 2008, 2009, 2010), bulletin 10221097: Transmission Kit with Torque Converter 1. All Promaster (VF) 3.6L/62TE equipped vehicles. If the transmission bracket to the transmission case fasteners are removed during servicing, the fasteners (Part Number 06511385A$…
- JEEP CHEROKEE (2014, 2015, 2016, 2017), bulletin 10221097: Transmission Kit with Torque Converter 1. All Promaster (VF) 3.6L/62TE equipped vehicles. If the transmission bracket to the transmission case fasteners are removed during servicing, the fasteners (Part Number 06511385A$…
Sources: NHTSA Office of Defects Investigation complaint database and manufacturer communications file, snapshots September 2026. A complaint or bulletin that mentions a code is a report about that vehicle, not a statement that the code has one cause.
Frequently asked questions
What is the difference between P0740 and P0741?
P0740 points at the electrical circuit: the solenoid, its wiring or the computer that drives it. P0741 means the circuit seems fine but the clutch isn't actually locking, which points more toward fluid, the valve body or the converter itself.
Can I drive with P0740?
Usually yes, for a while. The transmission still moves the car; it just never locks the converter. Keep trips short and get it checked soon if it slips, shifts harshly, gets stuck in one gear or the fluid smells burnt.
Will a new torque converter fix P0740?
Rarely. This is a circuit code, so the problem is usually electrical. Replacing the converter without testing the solenoid and wiring is the most expensive way to guess.
Can low transmission fluid cause P0740?
It can contribute on some transmissions, and it's a two-minute check, so do it first. But P0740 on its own usually means an electrical fault rather than a fluid problem.