U3575 code meaning
Coolant Mixing Valve Position Sensor Circuit
Network system Generic code U35xx codes Check engine light
What U3575 means
U3575 deals with wiring and signal of the sensor reporting how far the coolant mixing valve is open. GM lists feedback of the valve position, next to two temperature sensors, among the parts its stack outlet temperature control relies on. In Toyota's design the sensor is built into the valve and returns the angle of the valving element; since it can drift, the controller re-zeroes it against an end position before the coolant pump starts. If the signal is missing or shorted, the controller no longer knows where the valve stands and may regulate from temperatures alone or move the valve to a safe setting. No maker documents U3575 publicly. Probable results: a warning lamp and capped output. Faults in driving this valve fall under U3573.
U3575 at a glance
- Check engine lightYes, usually on
- Emissions testNot an emissions code
- Limp modePossible
- Repair difficultyHard
- Typical labor1 to 3 hours
- Clears after repairWhen cleared with a scanner
Symptoms of U3575
- Fuel cell system warning, MIL on
- Stack temperature regulated less precisely, reduced power
- Valve opening shown as invalid in live data
Common causes of U3575
- Most likelyOpen, short or moisture in the position sensor wiring or connector
- PossiblePosition sensor faulty (usually replaced together with the valve)
- Less likelySensor supply or ground missing
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Coolant mixing valve position sensorSensor wiring
What each part of U3575 means
| U | Network system: communication between the control modules (CAN bus). |
| 3 | Reserved range, usually generic. |
| 75 | The exact fault in that area. |
What to do next
- Note U3575 and any other codes stored with it: several codes together often point to one cause.
- Check for loose connectors and damaged wiring around the parts the code names.
- Check open recalls for your car: some faults are fixed for free by the dealer. Enter your VIN.
- Clear the code only after the repair. If it comes back, the fault is still there.
Buying a used car? Scan it for stored codes before you pay. A recently cleared memory can hide a problem.
Questions about U3575
What does U3575 mean?
U3575 means "Coolant Mixing Valve Position Sensor Circuit". U3575 deals with wiring and signal of the sensor reporting how far the coolant mixing valve is open. It is a generic code, so it means the same on every make.
Is it safe to drive with U3575?
Drive gently and only to a workshop. With U3575 the car can go into limp mode (reduced power) to protect itself.
Will U3575 fail an emissions test?
U3575 is not an emissions code, so on its own it usually does not fail an emissions test. Other stored codes or a lit check engine light still can.
How hard is U3575 to fix?
Difficulty: hard. A typical repair takes 1 to 3 hours of work. This is a job for a workshop.
Will U3575 clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.