Limp mode: Codes, Causes & Fixes
Limp mode (also called reduced power or fail-safe mode) is the vehicle protecting itself: the engine or transmission computer limits power, RPM or gear selection after detecting a fault. Typical triggers are throttle pedal or throttle body faults, turbo boost problems and transmission sensor or solenoid faults. Drive gently to a safe place or a shop; restarting may clear it temporarily, but the stored codes show the real cause.
165Codes
3.3Average severity
28%High or critical
4%DIY-friendly
Severity distribution
Most viewed
P0299
Powertrain
The turbo or supercharger isn't building the boost pressure the engine computer is asking for.
Moderate
P0606
Powertrain
The engine computer failed its own internal self-test – check its power and grounds before…
Moderate
P0700
Powertrain
The transmission computer found a fault and asked for the check engine light – read the TCM…
Moderate
P2002
Powertrain
The ECU thinks the diesel particulate filter isn't trapping soot properly — or it can't measure…
Moderate
U0073
Network
A module saw so many errors on CAN bus A that it shut off its own transmitter.
High
U0100
Network
Another module stopped hearing from the engine computer on the CAN network.
High
All codes (46)
P0001
Powertrain
The PCM can't drive the solenoid that meters fuel into the high-pressure pump. Often a no-start…
High
P0087
Powertrain
Measured fuel pressure has dropped well below what the engine computer is asking for.
High
P0200
Powertrain
The ECU found a fault in the injector control circuits that it can't pin on one cylinder, often…
High
P0216
Powertrain
The ECU can't control or confirm injection timing, usually on a diesel with an electronic…
High
P0217
Powertrain
The engine overheated. Stop driving: continuing can warp the head, blow the head gasket…
Critical
P0218
Powertrain
The transmission fluid got hotter than the computer allows, from heavy load, low fluid…
High
P0234
Powertrain
Boost rose above the safe limit the engine computer allows, so it may cut power to protect…
High
P0641
Powertrain
The PCM's shared 5-volt supply 'A' is missing or out of range – often one shorted sensor…
High
P0642
Powertrain
The PCM's 5-volt supply 'A' is being pulled below spec, usually by a short to ground in one…
High
P0730
Powertrain
The transmission computer sees input and output shaft speeds that don't fit the gear it…
High
P0751
Powertrain
Solenoid A is wired fine but its valve isn't doing its job, so gears are missing – often stuck…
High
P0756
Powertrain
Solenoid B isn't moving fluid the way the TCM expects – the car may pull away in 3rd or 4th.
High
P07A3
Ford · Powertrain
The PowerShift's odd-gear clutch isn't letting go when the TCM commands it open, so the car…
High
P0868
Powertrain
Measured transmission line pressure is below what the TCM commanded – clutches can slip…
High
P0894
Powertrain
The transmission computer measured slip inside the gearbox that shouldn't be there. Clutches…
High
P0A0F
Powertrain
The hybrid system spun the gas engine with its motor-generator to start it, but the engine…
High
P0A93
Powertrain
The inverter's separate coolant loop isn't carrying heat away – usually a dead electric…
High
P0A94
Powertrain
A hybrid voltage converter isn't delivering the voltage it should – on Toyotas, the boost…
High
P0AA6
Powertrain
High voltage is leaking toward the car body somewhere – an insulation fault that must be found…
High
P0AFA
Powertrain
Total high-voltage battery voltage dropped below the minimum the system allows, so power…
High
P1285
Ford · Powertrain
Ford's cylinder head temperature sensor reports the engine is overheating. Pull over and shut…
Critical
P1295
Hyundai · Powertrain
Hyundai's engine computer no longer trusts the electronic throttle and has cut power as…
High
P1299
Ford · Powertrain
The engine got so hot that the Ford PCM is shutting off fuel to cylinders to save it. Stop…
Critical
P1326
Hyundai · Powertrain
Hyundai's KSDS software heard vibration typical of worn rod bearings and put the engine in limp…
Critical
P1326
Kia · Powertrain
Kia's engine computer detected early rod-bearing wear through the knock sensor and capped…
Critical
P1682
Chevrolet · Powertrain
The engine computer's two ignition power feeds disagree, which can cause stalling or Reduced…
High
P1735
Volkswagen · Powertrain
The DSG control unit lost a valid signal from the sensor that tracks clutch 1 and locks out…
High
P175D
Volkswagen · Powertrain
The DSG computer saw clutch 1 let go while it was supposed to stay engaged, so it cut…
High
P1778
Nissan · Powertrain
The Jatco CVT's step motor is being commanded, but the pulley ratio isn't following it as it…
High
P17F0
Nissan · Powertrain
The TCM detected judder it blames on the CVT itself, usually belt or pulley slip inside…
High