P099B code meaning
Shift Solenoid G Control Circuit Low
Powertrain system Generic code P09xx codes Check engine light
What P099B means
Low-voltage fault, usually a short to ground, in the control circuit of shift solenoid G. Mitsubishi's 2019 service manual for a six-speed automatic uses it for the low-reverse brake shift solenoid: with transmission relay voltage at 2 V or more and the solenoid commanded on, the module sets P099B if the actual voltage stays below 3.7 V for 0.5 s. The check runs continuously; the solenoid is normally energised only in reverse and first-gear coasting. Nissan lists P099B as shift solenoid G in bulletin NTB15-037 for the 2012–2017 Versa, Versa Note and Sentra with the RE0F11A CVT and replaces the control valve when diagnosis confirms it. P099C is the high side, P09A0 the generic open.
P099B at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modePossible
- Repair difficultyHard
- Typical labor1 to 5 hours
- Clears after repairWhen cleared with a scanner
Symptoms of P099B
- Check engine light
- No reverse or no engine braking in first gear (Mitsubishi)
- Limp mode
Common causes of P099B
- Most likelyControl wire shorted to ground in harness or connector
- PossibleShorted solenoid inside the valve body
- Less likelyTransmission control module driver fault
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Shift solenoid gWiring harnessTCM
What each part of P099B 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. |
| 9B | The exact fault in that area. |
What to do next
- Note P099B 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 P099B
What does P099B mean?
P099B means "Shift Solenoid G Control Circuit Low". Low-voltage fault, usually a short to ground, in the control circuit of shift solenoid G. It is a generic code, so it means the same on every make.
Is it safe to drive with P099B?
Drive gently and only to a workshop. With P099B the car can go into limp mode (reduced power) to protect itself.
Will P099B fail an emissions test?
Yes, it can. P099B 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 P099B to fix?
Difficulty: hard. A typical repair takes 1 to 5 hours of work. This is a job for a workshop.
Will P099B clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.