P1549 fault code: what it means

P1549: Boost control solenoid (N75) open circuit or short to ground. Power loss or limp mode.

Engine and gearbox (powertrain) · Minor

Usual causes, most likely first

faulty boost control valve (N75)
broken or chafed wiring

P1549 by make

Audi

Boost control solenoid (N75) open circuit or short to ground. Power loss or limp mode.

Usual causes: faulty boost control valve (N75); broken or chafed wiring

Honda

Charging system high voltage. The manual calls for alternator replacement once confirmed; check for a 24 V jump first.

Usual causes: alternator regulator fault; 24 V jump start connected; poor battery or alternator connections

Skoda

Boost control solenoid (N75) open circuit or short to ground. Power loss or limp mode.

Usual causes: faulty boost control valve (N75); broken or chafed wiring

Volkswagen

Boost control solenoid (N75) open circuit or short to ground. Power loss or limp mode.

Usual causes: faulty boost control valve (N75); broken or chafed wiring

What the repair usually costs

Automatic transmission rebuild, 6-speed and up (sent to specialist)NZ$7,190–NZ$13,080 · A$6,190–A$11,830
DSG / dual-clutch mechatronic unit replacement (new or reman)NZ$4,300–NZ$7,160 · A$3,750–A$6,390
DSG mechatronic repair / rebuild (unit sent to specialist)NZ$2,070–NZ$4,800 · A$1,890–A$4,250
A/C compressor replace incl. drier and flush (European)NZ$1,560–NZ$3,200 · A$1,490–A$3,050

Not sure what P1549 means on your car? Ask Credov.

Before you clear it

Write the code down or photograph the scanner first. A code that comes straight back after clearing points to a fault that is still there. A car whose codes were cleared just before you arrived may be hiding one: the scanner's readiness monitors show "not ready" for a while after codes are cleared.

Researched by Credov from manufacturer and workshop sources. A fault code points to where a fault may be; a workshop confirms it with a diagnosis. Browse all fault codes.