P06AE — PCM/ECM/TCM Internal Temperature Sensor "B" Circuit High

OBD2 code P06AE flags a problem with the sensor and actuator circuits (PCM/ECM/TCM internal temperature sensor "B" circuit high). The car is usually drivable while you plan the repair. Common culprits: corroded, loose or damaged connector, open or shorted wiring in the circuit, control module driver fault.

powertrain (engine/transmission)

Is it safe to drive?

Short-term driving is OK In most cases the car remains drivable, possibly with reduced performance or a disabled auxiliary system. If symptoms include stalling, no-start or brake/steering warnings, treat it as urgent.

How to diagnose with an OBD scanner

Read the code and freeze frame Connect an OBD2 scanner, confirm P06AE is stored, and save the freeze frame data — it shows engine conditions when the fault was detected.
Check for companion codes and TSBs Related codes often reveal the real root cause. Also check manufacturer technical service bulletins (TSB) for your make and model — many P0xxx issues have factory fixes or software updates. Search by VIN on the manufacturer site or nhtsa.gov.
Inspect wiring and connectors Visually inspect the wiring harness and connectors related to the PCM/ECM/TCM internal temperature sensor "B" for damage, corrosion, chafing or poor contact.
Subsystem check With the PCM/ECM/TCM internal temperature sensor "B" disconnected, measure signal voltage at the harness connector: a high reading with the component unplugged indicates a short to power in the harness; if it drops to normal, the component itself is faulty.
Subsystem check Measure reference voltage, ground and signal continuity at the component connector.
Subsystem check Wiggle-test the harness while watching the signal in live data — dropouts reveal broken wires.
Verify the repair Clear the code, complete a full drive cycle including the conditions from the freeze frame, and confirm P06AE does not return.

Approximate repair cost

Repair cost depends on which component actually failed. Typical scenarios for P06AE (parts and labor, USD, independent shop rates): Repair wiring or connectors: $80–$250; Control module repair: $300–$1,000; Replace the faulty sensor or actuator: $150–$500. Overall, fixing P06AE usually costs between $80 and $1,000. An accurate diagnosis before buying parts saves money — the most expensive scenario is rarely the first one to check.

Common questions

How do I diagnose P06AE myself?

Start with a scan: confirm P06AE, save the freeze frame and note any companion codes. Then inspect the wiring and connectors related to the PCM/ECM/TCM internal temperature sensor "B", and verify the suspect component against live data before buying parts.

Will P06AE clear itself?

Sometimes P06AE clears after a few drive cycles if the fault was intermittent — for example a loose connector or a tank of bad fuel. The underlying cause usually remains, so the code tends to return. Clear it once; if it comes back, diagnose rather than erase it repeatedly.

Is it safe to drive with P06AE?

In most cases the car remains drivable, possibly with reduced performance or a disabled auxiliary system. If symptoms include stalling, no-start or brake/steering warnings, treat it as urgent.

What are the symptoms of P06AE?

Drivers most often notice: the affected system operates intermittently or not at all, possible limp mode depending on the affected component, increased fuel consumption in some cases, Check Engine Light on.

What is the most common cause of P06AE?

The most common causes are: corroded, loose or damaged connector, open or shorted wiring in the circuit, control module driver fault.

When your scan tool pulls code P06AE, the powertrain control module has detected that the internal temperature sensor circuit designated "B" is sitting at a voltage well above its normal operating range. P06AE falls under the powertrain fault family, which means it touches either the engine computer, transmission controller, or a combined unit that monitors temperature inside the module itself. The key phrase here is "Circuit High" — the module is seeing something close to full battery voltage on a circuit that should normally carry a much lower signal, usually a fraction of a volt that corresponds to a specific temperature reading.

The module does not set P06AE after a single bad reading. Automotive engineers designed these systems to ignore one-off electrical glitches, so the control unit waits for the fault to appear repeatedly under defined conditions before illuminating the Check Engine light. When P06AE does get stored, the freeze frame data that accompanies it is gold — it tells you engine load, RPM, coolant temperature, and vehicle speed at the exact moment the fault was detected. That snapshot becomes your target when you take the car for a test drive during diagnosis.

Common Symptoms of P06AE

The system governed by the affected internal temperature sensor operates intermittently or stops working entirely
Limp-home mode may activate depending on which component relies on that specific sensor signal
Fuel economy can increase noticeably on some vehicles when the module falls back to default compensation values
The Check Engine light remains illuminated until the fault is cleared and confirmed fixed

What Causes P06AE?

The root cause typically traces back to one of these failure points:

The internal temperature sensor "B" itself has failed and is pulling the signal line up to battery voltage
The signal wire between the sensor and control module has shorted directly to a power source
The ground return path for the sensor circuit is broken or has high resistance
A corroded, loose, or physically damaged connector is interrupting the ground reference
The control module driver that reads the sensor circuit has developed an internal fault
A blown fuse is depriving the circuit of its proper ground reference while leaving it partially powered
An adjacent sensor or actuator on the same circuit has failed in a way that drags the voltage high

How to Diagnose P06AE

Follow these steps in order to isolate the problem without replacing good parts:

Plug in your OBD2 scanner, confirm P06AE is present, and record all freeze frame data before clearing anything. Reproduce those exact driving conditions during your road test.
Pull all stored codes, not just P06AE. Related codes often point to the real culprit. Also search for technical service bulletins tied to this code on your manufacturer's website using your VIN — some vehicles have known software updates that resolve sensor circuit issues.
Perform a hands-on visual inspection of the wiring harness and connectors associated with the internal temperature sensor "B" circuit. Look for chafed insulation, bent pins, corrosion buildup, and any signs of water intrusion.
Disconnect the sensor and measure voltage at the harness side of the connector. If you still read high voltage with the sensor unplugged, the harness itself has a short to power. If the voltage drops to normal range, the sensor is the failed component.
Check reference voltage, ground integrity, and signal continuity at the component connector with a multimeter. Compare your readings against the specifications in your service manual.
Gently wiggle the harness while monitoring live data on your scanner. Any signal dropout or spike points to a broken wire hidden inside the insulation.
Clear the code, complete a full drive cycle covering the freeze frame conditions, and verify that P06AE does not return.

Repair Options and Costs

Tackle the cheapest possible cause first to avoid unnecessary expense:

Wiring repair or connector replacement: $80–$250
Control module internal repair: $300–$1,000
Sensor or actuator replacement: $150–$500

How Much Does Fixing P06AE Cost?

Your total bill hinges entirely on what component is actually at fault. Here are typical parts-and-labor scenarios at independent shop rates in USD:

Wiring harness repair or connector renewal typically runs $80–$250
Control module diagnosis and internal repair, when the PCB or drivers are damaged, lands between $300–$1,000
Replacing the faulty temperature sensor or its associated actuator usually costs $150–$500

Overall, expect to spend anywhere from $80 on the low end up to $1,000 if the control module itself requires attention. The smart move is to diagnose thoroughly before buying parts — the control module replacement is rarely the first thing to check, and a simple connector fix costs a fraction of the price.

Can You Drive with P06AE?

In most vehicles, P06AE does not leave you stranded. The car typically remains drivable, though you may notice reduced performance or an auxiliary system — such as transmission shift quality or certain engine safeguards — acting abnormally. If the vehicle develops stalling, a no-start condition, or warning lights related to brakes and steering, treat the situation as urgent and have it towed rather than risk driving it further.