P2859 code meaning
Clutch A Pressure Disengagement Performance/Too Low
Powertrain system Generic code P28xx codes Check engine light
What P2859 means
P2859 concerns the release side of clutch A: during a ratio change the control unit sees that the pressure handover is not working as planned, so the old and new power paths overlap or the wrong ratio persists. Mitsubishi's Mirage CVT shows how this is tested. With the first auxiliary ratio commanded, a fault is logged when the ratio stays within 10 % of the second ratio (0.900–1.100) for 0.5 s, if it leaves the plausible window (0.911 or less, 2.732 or more) for 0.2 s, or if the high clutch pressure switch reads on for 1.5 s at up to 10 km/h while its target pressure is zero. Nissan lists P2859 among the Kicks/Versa CVT pressure codes, and Mercedes-Benz calls it a general malfunction of multidisk clutch 1 on the 8G-DCT. Harsh or doubled shifts follow.
P2859 at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modePossible
- Repair difficultyWorkshop only
- Typical labor1 to 10 hours
- Clears after repairWhen cleared with a scanner
Symptoms of P2859
- Harsh, doubled or tied-up shifts
- Wrong gear stage held, engine speed too low or too high
- Transmission warning and emergency program
Common causes of P2859
- Most likelyOutgoing clutch not venting in time, so both elements carry torque
- PossibleSticking pressure control solenoid or valve in the valve body
- Less likelyClutch pressure switch reporting pressure that is not there
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Clutch aClutch actuator aTransmission pump
What each part of P2859 means
| P | Powertrain system: engine, fuel system, ignition, emissions and transmission. |
| 2 | Generic code (second SAE range): it means the same on every make. |
| 8 | Area: transmission. |
| 59 | The exact fault in that area. |
What to do next
- Note P2859 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 P2859
What does P2859 mean?
P2859 means "Clutch A Pressure Disengagement Performance/Too Low". P2859 concerns the release side of clutch A: during a ratio change the control unit sees that the pressure handover is not working as planned, so the old and new power paths overlap or the wrong ratio persists. It is a generic code, so it means the same on every make.
Is it safe to drive with P2859?
Drive gently and only to a workshop. With P2859 the car can go into limp mode (reduced power) to protect itself.
Will P2859 fail an emissions test?
Yes, it can. P2859 is emissions-related, so most inspection programs fail a car while it is stored or while the check engine light is on.
How hard is P2859 to fix?
Difficulty: workshop only. A typical repair takes 1 to 10 hours of work. This is a job for a workshop.
Will P2859 clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.