P0700 Code: Transmission Control System Malfunction
The transmission computer found a fault and asked for the check engine light – read the TCM codes next.
At a glance
Severity: Moderate
- Meaning
- Transmission Control System Malfunction
- System
- Transmission · Powertrain
- Safe to drive?
- With caution
- Typical repair cost
- $150–$5,500
- DIY difficulty
- Moderate
P0700 is a messenger, not a diagnosis. When the transmission control module (TCM) stores a fault, it asks the engine computer to turn on the check engine light, and the engine computer records P0700 as the flag. The real information – a shift solenoid, speed sensor, slip-ratio or pressure code – sits in the TCM's own memory, which many basic code readers can't access. Diagnosis therefore starts with a scan tool that can read transmission codes and live data, plus a check of fluid level and battery voltage.
Can I keep driving? If the transmission still shifts normally, drive gently to a shop. If it is stuck in one gear, slips or flares between shifts, keep speeds low and trips short – driving a slipping automatic quickly burns up clutches.
How to read P0700
- P Powertrain
- 0 Generic (SAE)
- 7 Transmission
- 00 Specific fault
Symptoms
- Check engine light with only P0700 on a basic code reader
- Transmission stuck in one gear (often 2nd or 3rd) – limp mode
- Harsh, late or erratic shifts
- Slipping or rpm flare between gears
- Delayed engagement into Drive or Reverse
- Transmission temperature or 'service transmission' warning
- Speedometer or cruise control acting up
Possible causes
Ranked by how often each cause is behind this code (editorial estimate).
- Shift or pressure-control solenoid fault stored in the TCM
- Low, burnt or wrong-spec transmission fluid
- Input or output speed sensor or its wiring
- Internal mechanical wear setting slip or gear-ratio codes
- Low system voltage, poor TCM ground or corroded connector
- TCM hardware or software fault
Diagnosis step by step
Read the TCM with a capable scan tool
Use a scanner that can access transmission codes – many shops and some parts stores can. Write down every TCM code and its freeze frame; that code, not P0700, tells you what to test next.
Tools: OBD-II scanner
Check fluid level and condition
Follow the owner's manual procedure – many newer automatics have no dipstick and are checked at a set temperature through a fill or check plug. A burnt smell, dark brown color or debris means internal wear.
Tools: Flashlight, Towels & shallow pan
Verify battery and charging voltage
Transmission modules are sensitive to low voltage; a weak battery or alternator can set solenoid and communication codes. Confirm about 12.6 V at rest and 13.5–14.8 V running.
Tools: Multimeter
Inspect TCM and transmission connectors
Check the harness connector at the transmission case and at the TCM for fluid wicking, corrosion and loose pins. Fluid inside a connector often means a leaking internal pass-through seal.
Tools: Flashlight, Screwdriver
Test the component the TCM code names
Measure the flagged solenoid or sensor at the connector and compare with specs, then road-test while watching input/output speed, commanded gear and line pressure data.
Tools: Multimeter, OBD-II scanner
Check for updates and relearns
Some transmissions need a software update or an adaptive relearn after repairs or a fluid service. Skipping it can cause harsh shifts that set the same codes again.
Tools: OBD-II scanner
Where the parts are
- 1Battery
- 2Alternator
- 3Engine computer (ECM)
- 4CAN bus
- 5Transmission
- 6Wheel speed sensor
- 7High-voltage battery
Repair options & costs
| Repair | DIY? | Estimated cost |
|---|---|---|
| Transmission fluid and filter service | No | $150–$400 |
| Replace input or output speed sensor | No | $150–$400 |
| Replace shift solenoid or solenoid pack | No | $300–$900 |
| Replace and program TCM | No | $500–$1,500 |
| Rebuilt or remanufactured transmission | No | $2,500–$5,500 |
Rough US estimates for parts and labor; shop rates vary by region. Not a quote.
Notes by brand
Nissan
On Nissans with a CVT, P0700 usually accompanies CVT-specific codes stored in the transmission module, such as judder or ratio faults. Fluid condition and the correct Nissan CVT fluid matter a lot; generic fluid can cause shudder and repeat codes.
Field data
| Chevrolet | 52 | ||
|---|---|---|---|
| GMC | 21 | Acadia, Sierra 1500, Terrain | |
| Chrysler | 14 | 300, Pacifica, Sebring | |
| Subaru | 11 | Outback, Forester, IMPREZA WRX/STI | |
| Dodge | 7 | Charger, Avenger, Caliber | |
| Jeep | 6 | Commander, Compass, Grand Cherokee | |
| Audi | 2 | RS5, S5 CABRIOLET | |
| Nissan | 2 | Rogue, Xterra |
Source: NHTSA Complaints API (US government open data), analyzed by DTC mention.
Emissions / smog test impact
Will fail
P0700 means the check engine light is on, so the vehicle fails an OBD emissions test until the underlying TCM fault is repaired and the readiness monitors have run again.
Frequently asked questions
Why does my code reader only show P0700?
Basic readers only see the engine computer's generic codes. P0700 is the engine computer saying the transmission module has a fault; you need a scanner that can talk to the TCM to see the actual code.
Can low transmission fluid cause P0700?
Yes, indirectly. Low fluid causes slipping or pressure problems, the TCM stores a slip or pressure code, and that triggers P0700. Always check the level before replacing parts.
Will clearing the code get me out of limp mode?
Sometimes, temporarily. If the fault is real, the TCM detects it again and goes back into limp mode. Clearing also erases freeze-frame data a shop needs, so read and record codes first.
Does P0700 mean my transmission is failing?
Not necessarily. Many P0700 cases turn out to be a sensor, a solenoid, wiring or low voltage. Only slip, ratio or pressure codes combined with burnt fluid and debris point toward internal failure.