P0727: Engine speed signal missing from the transmission's input
Engine speed input circuit no signal
Severity: Severity not verified — if the car runs badly, have it inspected
We found no source that rates P0727. TroubleCodes.net lists transmission shift symptoms for related circuits, so how it affects driving depends on the vehicle.
It gets more serious if:
- Inspect soon: If the transmission shifts harshly, sticks in one gear, goes into limp mode, or the engine stalls, have it inspected soon.
P0727 in short
P0727 means the computer receives no engine speed signal for transmission control. A faulty engine speed or crankshaft sensor, damaged wiring or connectors, or a poor link between the engine and transmission computers are the usual causes. Shifts may be harsh or the car may go into limp mode.
The transmission computer uses engine speed to time shifts and manage the torque converter. P0727 sets when that engine speed signal is missing entirely.
TroubleCodes.net lists the engine speed sensor, wiring and connectors, the PCM to TCM connections and, rarely, the modules. On some VW and Audi-group cars the crankshaft position sensor serves as the engine speed sensor, and a failure can also cause a no-start.
Most likely causes
These are general causes for this code across vehicles. None is specific to one make or model.
Cause 1: Faulty engine speed or crankshaft position sensor
Common general cause- Why it ranks here
- TroubleCodes.net lists the sensor first and notes the crankshaft sensor can double as the speed source.
- What would change this
- Rises if the engine has no tach signal or cranks without starting. Falls if the engine speed reads normally on a scan tool.
Cause 2: Damaged, corroded or disconnected wiring or connectors
Common general cause- Why it ranks here
- TroubleCodes.net lists wiring, connectors and the PCM to TCM connection.
- What would change this
- Rises if a connector is loose or corroded. Falls if the signal wiring tests good.
Cause 3: Engine or transmission computer fault
Possible — needs testing- Why it ranks here
- TroubleCodes.net says module failure is rare.
- What would change this
- Rises only after sensor and wiring test good. Falls if a sensor or wiring fault is found.
What to test first
Start at step 1. Each result tells you what it means and where to go next.
Step 1: Read the stored codes, then compare engine speed on the scan tool with the dashboard tach while the engine runs.
Warning:Keep hands and tools clear of belts and the fan with the engine running, and keep the vehicle in park with the parking brake set.
IfEngine speed reads zero or drops out on the scan tool
It meansThe engine speed signal is missing. Inspect the sensor and wiring.
IfEngine speed reads normally
It meansThe fault may be in the link to the transmission computer. Have a shop test it.
Points to: Damaged, corroded or disconnected wiring or connectors
Step 2: Inspect the engine speed or crankshaft sensor connector and harness for damage, and check the signal wiring to the computers.
Warning:Engine bay parts and the exhaust can be hot, and the fan can start without warning. Disconnect the battery before unplugging modules.
IfWiring or a connector is damaged or corroded
It meansRepair it.
Points to: Damaged, corroded or disconnected wiring or connectors
IfWiring is good but the sensor signal is missing
It meansTest or replace the sensor.
Points to: Faulty engine speed or crankshaft position sensor
IfSensor and wiring test good
It meansHave a shop test the computers.
Symptoms
- Check engine light on
- Harsh, erratic or unpredictable shifts Gets more serious: stop and have it checked.
- Stuck in one gear or limp mode Gets more serious: stop and have it checked.
- Stalling at low speed, or no-start on cars where the crankshaft sensor is the speed source Gets more serious: stop and have it checked.
How to fix
Step 1: With the engine off, check that the engine speed sensor connector is seated and the wiring is not damaged.
Parts and cost context
- Transmission control module (TCM):Test the sensor, switch and wiring first. Labour varies; get a quote.
Labor varies by vehicle and shop; get a quote before you approve a repair.
Compare used part prices on PartPriceGuideOn your vehicle
We don't have reviewed vehicle-specific evidence for P0727 yet. The causes and tests above apply across vehicles.
Related codes
P0727 questions
What does P0727 mean?
The engine speed input circuit has no signal. The transmission computer is not getting engine speed.
Can I drive with P0727?
It may shift harshly, go into limp mode or stall, so have it checked soon rather than driving far.
Sources and review
- Last reviewed
- Written by
- Saurabh K.
- Editorial review
- Pending
- Technician review
- Technician review pending
This page explains what a code usually means; it is not a substitute for a professional inspection. How we source and review · Report an error