U064ENetwork · Lost communicationGeneric (SAE) code

U064E: Lost Communication With EGR Cooler Bypass Position Sensor Bank 1

The vehicle bus reports loss of communication with smart EGR cooler bypass position sensor on bank 1. EGR cooling switching cannot be verified; emissions strategy may revert to fully cooled mode.

Typical labor cost
$65–$375 est.
30 min–3 h at an assumed $125/hr · parts extra · use your rate
Most common fix
Bus wiring open or shorted
DIY difficulty: Moderate · usually a shop job
01 —What it means

What U064E means

U064E is a generic OBD-II network code in the lost communication group. In plain English: a control module stopped receiving messages from the EGR Cooler Bypass Position Sensor Bank 1 on the vehicle’s data network. Bank 1 is the side of the engine with cylinder 1 (inline engines only have bank 1).

U
Network
0
Generic (SAE)
6
Subsystem group
4E
Specific fault
How to read U064E. We group it under Lost communication.
Check engine light
Usually on
Emissions-related
Yes — can fail inspection
Limp mode possible
Not typical
Drive cycle to clear
Required
Code data: OBDex (CC0)

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02 —Symptoms

Symptoms

What drivers typically notice
  • Multiple warning lights may illuminate
  • Affected modules may go into limp mode or shut down
  • Specific functions inoperative depending on module
  • Diagnostic tools may show communication faults
Code data: OBDex (CC0)
03 —Causes

Common causes

Ranked from most to least likely
  1. 01Bus wiring open or shortedMost likely
  2. 02Module without power or groundPossible
  3. 03Module failedPossible
Code data: OBDex (CC0)
04 —Severity

Can I drive with U064E?

Moderate

Usually yes, for a short time.

The car will often drive normally, but get it diagnosed soon. Left alone it can raise fuel use and emissions and will fail an OBD inspection. If you notice rough running, warning lights flashing, overheating or a burning smell, stop driving.

Why we rate it moderate

  • Turns on the check engine light
  • Emissions-related: will usually fail an OBD inspection
  • Needs a drive cycle to confirm a repair

Severity is our rule-based rating from the code’s flags in OBDex and the system it affects, not an inspection of your car. If the check engine light is flashing, or you notice overheating, low oil pressure, or brake or steering problems, stop driving and get help.

Code data: OBDex (CC0)
05 —Diagnosis

How to diagnose U064E

General procedure — follow the service manual for your vehicle
  1. 1

    Confirm the code and save freeze-frame data

    Read the codes with an OBD-II scan tool and note every code, not just U064E. Save the freeze-frame data (speed, load, temperature when the fault set) before clearing anything; it tells you when the fault happens.

  2. 2

    Fix other faults first

    If other codes are stored, start with power-supply, sensor-circuit and communication codes. They can cause this code as a side effect.

  3. 3

    Check module power, ground and the data bus

    Confirm the module named in the code has battery voltage, ignition feed and a good ground. With the battery disconnected, a healthy CAN bus usually measures about 60 ohms between CAN-High and CAN-Low at the OBD port. Inspect connectors for corrosion and pushed-out pins.

  4. 4

    Test the likely causes in order

    Start with the most likely cause and work down: Bus wiring open or shorted; module without power or ground; module failed. Test before replacing parts.

  5. 5

    Check for recalls and service bulletins

    Look up recalls for your exact vehicle with its VIN, and ask a dealer about technical service bulletins (TSBs). Manufacturers sometimes issue software updates or extended warranties for known faults.

  6. 6

    Clear the code and verify the repair

    After the repair, clear the code and complete a full drive cycle (cold start, idle, steady highway cruise, deceleration). The code is fixed when the related readiness monitor completes without it returning.

Code data: OBDex (CC0)
06 —Cost

U064E repair cost estimate

Labor only — set your local shop rate
Labor estimate for U064E
$65–$375
30 min–3 h of labor × $125/hr (assumed rate) · parts extra

Estimate, not a quote. Labor times are typical ranges for this code from OBDex, and $125/hr is an assumed rate. Shop rates and labor times vary by vehicle and region. Diagnosis time may be billed separately.

DIY difficulty
Moderate
Good DIY job?
Usually a shop job

Needs a scan tool and some experience with testing.

Code data: OBDex (CC0)
07 —Components

Parts and systems involved

  • EGR cooler bypass position sensor bank 1
  • Vehicle bus wiring
Code data: OBDex (CC0)
09 —FAQ

U064E FAQ

What does U064E mean?

U064E means “Lost Communication With EGR Cooler Bypass Position Sensor Bank 1”. The vehicle bus reports loss of communication with smart EGR cooler bypass position sensor on bank 1. EGR cooling switching cannot be verified; emissions strategy may revert to fully cooled mode.

Is U064E serious? Can I keep driving?

We rate U064E as moderate severity. Usually yes, for a short time. The car will often drive normally, but get it diagnosed soon. Left alone it can raise fuel use and emissions and will fail an OBD inspection. If you notice rough running, warning lights flashing, overheating or a burning smell, stop driving.

What causes U064E?

The most common causes, from most to least likely: Bus wiring open or shorted; Module without power or ground; Module failed. Test before replacing parts, because several causes can set the same code.

How much does it cost to fix U064E?

Typical labor is about $65–$375 at an assumed $125/hour shop rate, plus parts. That is an estimate, not a quote: labor times and rates vary by vehicle and region, and diagnosis may be billed separately.

Can I fix U064E myself?

DIY difficulty is moderate. Most owners leave this to a shop because it needs involved testing or specialist tools. Always confirm the cause before buying parts.

Will U064E clear itself?

Once the fault is fixed, the check engine light usually goes off by itself after the system passes its self-test over several drive cycles. Clearing the code with a scan tool resets readiness monitors, so an inspection station may turn you away until a full drive cycle is completed.

Code data: OBDex (CC0)