P0959 code meaning
Auto Shift Manual Mode Circuit Intermittent
Powertrain system Generic code P09xx codes Check engine light
What P0959 means
The signal reporting the selector lever in the manual gate drops out or toggles briefly while the lever is not moved, so the transmission control switches between manual and automatic mode on its own. The voltage is not stuck out of range as with P0957 or P0958 but jumps. Loose connector pins at the lever, a harness that flexes with the shifter or a worn microswitch are typical. A Hyundai patent shows such a microswitch actuated by the lever's sideways movement, a Nissan patent the two-contact mode switch. No manufacturer documents this exact code publicly; CARB requires circuit checks. P0955 is the general fault, P0954 the intermittent fault of the up/down circuit.
P0959 at a glance
- Check engine lightYes, usually on
- Emissions testNot an emissions code
- Limp modeNot expected
- Repair difficultyMedium, DIY possible
- Typical labor0.5 to 3 hours
- Clears after repairWhen cleared with a scanner
Symptoms of P0959
- Manual mode switches on or off by itself
- Gear display flickers between D and manual gear
- Fault often appears on rough roads
Common causes of P0959
- Most likelyLoose pins in the selector lever connector
- PossibleWorn or bouncing mode microswitch
- PossibleHarness damaged where it moves with the lever
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Auto shift manual switchWiring harnessTCM
What each part of P0959 means
| P | Powertrain system: engine, fuel system, ignition, emissions and transmission. |
| 0 | Generic code: it means the same on every make (SAE standard). |
| 9 | Area: transmission. |
| 59 | The exact fault in that area. |
What to do next
- Note P0959 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 P0959
What does P0959 mean?
P0959 means "Auto Shift Manual Mode Circuit Intermittent". The signal reporting the selector lever in the manual gate drops out or toggles briefly while the lever is not moved, so the transmission control switches between manual and automatic mode on its own. It is a generic code, so it means the same on every make.
Is it safe to drive with P0959?
Usually yes, for a short time, if the check engine light is steady and the car drives normally. If the light flashes or the car runs badly, stop and have it checked.
Will P0959 fail an emissions test?
P0959 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 P0959 to fix?
Difficulty: medium. A typical repair takes 0.5 to 3 hours of work. A careful DIY repair is possible with basic tools and a scanner.
Will P0959 clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.