P23A4

Exhaust Heat Exchanger Exhaust Bypass Valve B Control Circuit High

Severity

⚠️ Medium

Can you drive?

Yes, but get it checked soon

Approx. repair cost

$28–89 (est.)

Symptoms

Check Engine Light Is On
Deterioration of interior heating
Increased fuel consumption
Reduced engine power
Unstable operation at idle

Causes

Open or short circuit in valve control circuit
Heat exchanger bypass valve malfunction
Problems with the relay or circuit fuse
Corrosion or poor contact in connectors
Engine control unit malfunction

How to Fix

Check valve control circuit integrity
Check valve resistance and operation
Inspect connectors and contacts for corrosion
Check relays and circuit fuses
Replace bypass valve if necessary

Related codes

P23A0 P23A1 P23A2