Engine-Codes - Generic - P154B

P154B - Intake Air Heater Voltage Signal Circuit

Repair Importance Level: 3/3
Repair Difficulty Level: 3/3  What is this?
Table of contents

P154B Possible Causes

  • Faulty Intake Air Heater
  • Intake Air Heater harness is open or shorted
  • Intake Air Heater circuit poor electrical connection

How is the P154B code repair?

Start by checking the "Possible Causes" listed above. Visually inspect the related wiring harness and connectors. Check for damaged components and look for broken, bent, pushed out, or corroded connector's pins.

What is the cost to diagnose the P154B code

Labor: 1.0

The cost to diagnose the P154B code is 1.0 hour of labor. The auto repair labor rates vary widely across the country, and even within the same city. Most auto repairs shops charge between $75 and $150 per hour.
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Possible Symptoms

  • Engine Light ON (or Service Engine Soon Warning Light)

P154B Meaning

The Intake Air Heater (IAH) is located in the air inlet tube and is used to warm the incoming air to aid in starting the engine and for proper cylinder combustion. The Glow Plug Control Module (GPCM) will command the IAH ON when the engine coolant temperature is below 40°C (104°F). The IAH is connected to the GPCM by the following circuits:
- The IAH temperature signal circuit
- The IAH command 1 circuit
- The IAH command 2 circuit
- The IAH voltage signal circuit
- The IAH current signal circuit
- The IAH feedback signal circuit

More Information

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