P1418 GMC - Secondary Air Injection System Relay 'A' Control Circuit High

Repair Importance Level: 3/3
Repair Difficulty Level: 3/3  What does this mean?

P1418 GMC Possible Causes

  • Faulty Secondary Air Injection (AIR) System Relay
  • Secondary Air Injection System Relay harness is open or shorted
  • Secondary Air Injection System Relay circuit poor electrical connection

First diagnose P1418 GMC code

    Check 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 terminals.

Cost of diagnosing the P1418 GMC code

    Labor: 1.0

    The cost of diagnosing the P1418 GMC 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.

P1418 GMC Possible Symptoms

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

P1418 GMC Meaning

A Secondary Air Injection (AIR) pump is used on this vehicle to lower tail pipe emissions on start-up. The Powertrain Control Module (PCM) supplies a ground to the AIR pump relay, which energizes the AIR pump. The PCM monitors the HO2S voltages to diagnose the AIR system. During the AIR test, the PCM activates the AIR pump during closed loop operation. When the AIR is activated, the PCM monitors the HO2S voltages and short term fuel trim values for both banks of the engine. If the AIR system is operating properly, the HO2S voltages should go low and the short term fuel trim should go high.
OBDII Code P1418 GMC - Secondary Air Injection System Relay 'A' Control Circuit High - Engine-Codes.com

P1418 GMC More Information

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