P34BB code meaning
B Camshaft Position Actuator Temperature Sensor Circuit High Bank 2
Powertrain system Generic code P34xx codes Check engine light
What P34BB means
P34BB is stored when the bank 2 exhaust actuator's temperature signal stays above its window – typically a broken signal line, a loosened ground connection or contact with a supply wire. Because the module can no longer see how warm the actuator driver is, it lacks what it needs to protect it; Aisin's design, for comparison, ends its current reduction only after the reading has stayed below a return threshold for some time. With the value missing, the exhaust phaser on this bank will usually be kept in a safe position, so the warning lamp is often the only sign. No manufacturer publication covers P34BB, and NTN-SNR simply calls it too high a signal on the outlet side, second bank. High fault on bank 1: P34B7; low on bank 2: P34BA.
P34BB at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modePossible
- Repair difficultyMedium, DIY possible
- Typical labor0.5 to 3.5 hours
- Clears after repairWhen cleared with a scanner
Symptoms of P34BB
- Malfunction indicator lamp lit
- Bank 2 exhaust cam held in a safe position
Common causes of P34BB
- Most likelySignal line broken or sensor ground loose
- PossibleSignal line touching a supply wire
- Less likelySensor open inside the bank 2 actuator
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Cam actuator b temp sensor b2Sensor wiring
What each part of P34BB means
| P | Powertrain system: engine, fuel system, ignition, emissions and transmission. |
| 3 | Mixed range: generic and manufacturer-specific codes. |
| 4 | Area: auxiliary emission controls (catalytic converter, EGR, EVAP). |
| BB | The exact fault in that area. |
What to do next
- Note P34BB 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 P34BB
What does P34BB mean?
P34BB means "B Camshaft Position Actuator Temperature Sensor Circuit High Bank 2". P34BB is stored when the bank 2 exhaust actuator's temperature signal stays above its window – typically a broken signal line, a loosened ground connection or contact with a supply wire. It is a generic code, so it means the same on every make.
Is it safe to drive with P34BB?
Drive gently and only to a workshop. With P34BB the car can go into limp mode (reduced power) to protect itself.
Will P34BB fail an emissions test?
Yes, it can. P34BB 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 P34BB to fix?
Difficulty: medium. A typical repair takes 0.5 to 3.5 hours of work. A careful DIY repair is possible with basic tools and a scanner.
Will P34BB clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.