P0249: Wastegate solenoid B signal too low
Turbocharger wastegate solenoid B circuit low
Severity: Severity not verified — if the car runs badly, have it inspected
The sources read give the meaning and causes but do not say how urgent this code is.
P0249 in short
P0249 is a turbocharger wastegate fault code. The wastegate valve B circuit voltage is lower than expected, or the computer found a fault on solenoid B. Wiring, the solenoid itself and, rarely, the engine computer are the usual causes. The sources read do not rate its urgency, so have it scanned and checked.
The wastegate controls how much exhaust bypasses the turbo, which sets boost. The computer drives it through a solenoid (also called a regulating valve) and watches that circuit. P0249 is titled "Turbocharger wastegate solenoid B circuit low" by the Delaware DMV list and "Turbocharger (TC) wastegate regulating valve B circuit low" by TroubleCodes.net.
TroubleCodes.net lists the wastegate solenoid, wiring and connectors, and the engine computer as probable causes, with the computer described as unlikely.
Most likely causes
These are general causes for this code across vehicles. None is specific to one make or model.
Cause 1: Wiring or connector fault on the solenoid circuit
Common general cause- Why it ranks here
- TroubleCodes.net lists wiring short to ground and defective or moisture-affected connectors for this circuit fault.
- What would change this
- Rises if the harness or connector shows damage or moisture. Falls if the wiring tests good.
Cause 2: Wastegate solenoid (B) failure
Common general cause- Why it ranks here
- The valve itself is named as a probable cause by TroubleCodes.net.
- What would change this
- Rises if the wiring is good and the valve resistance is off. Falls if the valve tests normal.
Cause 3: Engine computer fault
Possible — needs testing- Why it ranks here
- Listed as a probable cause but described as unlikely, so it ranks last.
- What would change this
- Rises only after wiring and valve both test good. Falls if either is faulty.
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 and inspect the wastegate solenoid B connector and wiring for damage, moisture or corrosion.
Warning:Keep hands and tools clear of the hot turbo and exhaust; let the engine cool first.
IfWiring or connector damage is found
It meansRepair it and retest.
Points to: Wiring or connector fault on the solenoid circuit
IfWiring looks fine
It meansTest the solenoid.
Step 2: Check solenoid resistance against the maker's spec; zero or infinite is a fault. Confirm supply voltage and ground at the connector.
Warning:Probing a live connector can short the circuit and damage the engine computer; a shop should do it.
IfThe solenoid fails the test
It meansReplace the solenoid.
IfSolenoid and wiring both test good
It meansSuspect the engine computer.
Symptoms
- Check engine light
Compare with: Check engine light with loss of power
How to fix
On your vehicle
We don't have reviewed vehicle-specific evidence for P0249 yet. The causes and tests above apply across vehicles.
Related codes
No curated relationships for P0249 yet.
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