P0793: No signal from the intermediate shaft speed sensor

Intermediate shaft speed sensor A circuit, no signal

Severity: Inspect soon

Honda owners report P0793 on cars that suddenly stopped driving, including one where fluid looked overheated. Treat it as a transmission fault that can strand the car.

It gets more serious if:

Stop: Stop driving if the car stalls, will not move in Drive or Reverse, or the D indicator flashes. Honda HR-V owners report this with P0793.

Source: how we rate severity

P0793 in short

P0793 means the transmission computer is getting no signal from the intermediate shaft speed sensor. On Honda CVT cars owners report it before the transmission stopped driving. Causes are the sensor or its wiring, a failing transmission, or the computer. Have it inspected soon; stop if the car stalls or will not move.

The transmission computer compares the speeds of several rotating parts to judge gear ratio and slip. P0793 means the intermediate shaft speed sensor gave no signal at all, which can mean a dead sensor, a broken wire or a shaft that is not turning as expected.

Most reports we found are Honda CVT cars. Civic and HR-V owners say the code came with a transmission that stopped driving; one dealer replaced the pulley speed sensor and the problem stayed, and the D light began to flash. This suggests the sensor can be a symptom of a larger transmission failure.

Infiniti has a bulletin for 2019 QX50 where P0793 and other codes stay stored as permanent codes after a repair; the fix is a new transmission computer. Audi lists P0793 on the 2023 RS 3 in its own bulletin.

Most likely causes

Cause 1: Speed sensor, connector or wiring
Common general cause
Why it ranks here
TroubleCodes.net lists wiring, connection, short to ground and the sensor itself as causes; Honda dealers replaced the pulley speed sensor on an HR-V.
What would change this
Rises if live data shows no speed signal and a wiring or sensor test fails. Falls if the signal is present and plausible, or the sensor swap did not help.
Cause 2: Internal CVT failure
Supported by vehicle data
Why it ranks here
Civic and HR-V owners report P0793 with a total loss of drive and hot-looking fluid, and dealers quoted replacements. Complaint data only.
What would change this
Rises if the fluid is dark or burnt, the car will not drive in Drive or Reverse, or the D light flashes. Falls if the car drives normally and the sensor test fails.
Cause 3: Transmission computer holding a permanent code (2019 QX50)
Supported by vehicle data
Why it ranks here
Infiniti ITB20-027 replaces the computer when permanent codes including P0793 will not erase after the standard procedure. This applies only when no other codes are stored.
What would change this
Rises only on a 2019 QX50 where the code will not erase and no other codes exist. Falls on any other vehicle.
How to test the transmission control module (tcm)

What to test first

Start at step 1. Each result tells you what it means and where to go next.

Step 1: Read all codes and the transmission live data, including the intermediate shaft speed reading, with a scan tool that reads the transmission module.
Low riskTool: scan tool that reads the transmission module
- IfThe speed reading is zero or erratic while driving
  It meansTest the sensor and its wiring.
  Go to step 2
- IfThe speed reads plausibly but the code is stored
  It meansLook for intermittent faults or damage; see test drive.
  Go to step 3
Step 2: Have the sensor connector, wiring and sensor checked for damage, corrosion and the correct signal.
Best left to a shopTool: multimeter, scope or scan tool
Warning:The sensor sits on the transmission under the car and the fluid can be hot. Leave this to a shop.
- IfDamage or a bad signal is found
  It meansRepair or replace the sensor or wiring.
  Points to: Speed sensor, connector or wiring
- IfThe sensor and wiring are good
  It meansCheck the transmission condition.
  Go to step 3
Step 3: Have the transmission fluid condition and the transmission itself checked, including whether the car drives in Drive and Reverse.
Best left to a shop
Warning:A transmission that may stop driving can leave you stranded. Do not drive it if the D light flashes.
- IfThe fluid is dark or burnt, or the car will not drive
  It meansInternal damage is likely.
  Points to: Internal CVT failure
- IfOn a 2019 QX50 the code will not erase and nothing else is stored
  It meansAsk Infiniti about ITB20-027.
  Points to: Transmission computer holding a permanent code (2019 QX50)

Symptoms

Check engine or transmission warning light
Sluggish car, sound of the transmission changing gears oddly
Stalling
Car will not move in Drive or Reverse, or the D light flashes Gets more serious: stop and have it checked.

How to fix

Step 1: Ask a dealer whether a transmission software update or bulletin applies to your VIN for P0793.

Parts and cost context

Transmission control module (TCM):The computer is only the answer on a 2019 QX50 per Infiniti; otherwise the sensor or transmission is more likely. Labor varies; get a quote.

Labor varies by vehicle and shop; get a quote before you approve a repair.

Compare used part prices on PartPriceGuide

On your vehicle

Honda

2015 · Civic
Supported by vehicle data
A dealer read P0793 (intermediate shaft speed sensor A circuit, no signal) on a CVT that failed and had hot-looking fluid.
2016–2022 · HR-V
Supported by vehicle data
Owners report P0793 with loss of drive, stalling and a flashing D light; one dealer replaced the pulley speed sensor without a fix.

Infiniti

2019 · QX50
Supported by vehicle data
Infiniti ITB20-027 covers P0793 among permanent codes that will not erase.

ITB20-027Status unverified
Permanent DTC set in TCM and will not erase (includes P0793)
2019qx50 · NHTSA 10185379
If only the listed DTCs, including P0793, are stored and will not erase after the standard procedure, the action is to replace the TCM.
We couldn't confirm whether this bulletin is still current, so it doesn't count as confirmation.

All Transmission codes

P0793 questions

Is the intermediate shaft speed sensor the usual fix for P0793?

Not always. On Honda CVT cars owners report the sensor being replaced without a fix because the transmission itself had failed.

Sources and review

NHTSA complaint ODI 11322773: 2015 Honda Civic, P0793 — NHTSA Office of Defects Investigation (consumer complaint)
NHTSA complaint ODI 11653707: 2020 Honda HR-V, P0171 and P0793 — NHTSA Office of Defects Investigation (consumer complaint)
P0793 – Intermediate Shaft Speed Sensor – No Signal — TroubleCodes.net
NHTSA complaint ODI 11761109: 2022 Honda HR-V, P0793 — NHTSA Office of Defects Investigation (consumer complaint)
Infiniti ITB20-027: permanent DTC set in TCM and will not erase (2019 QX50) — Infiniti (filed with NHTSA)

Last reviewed: October 16, 2026
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

Severity: Inspect soon

Most likely causes

Cause 1: Speed sensor, connector or wiring

Cause 2: Internal CVT failure

Cause 3: Transmission computer holding a permanent code (2019 QX50)

What to test first

Step 1: Read all codes and the transmission live data, including the intermediate shaft speed reading, with a scan tool that reads the transmission module.

Step 2: Have the sensor connector, wiring and sensor checked for damage, corrosion and the correct signal.

Step 3: Have the transmission fluid condition and the transmission itself checked, including whether the car drives in Drive and Reverse.