Engine-Codes - Cadillac - P1509 CADILLAC

P1509 CADILLAC - Idle Speed High Idle Air Control System Not Responding

Repair Importance Level: 3/3
Repair Difficulty Level: 2/3  What is this?
Table of contents

P1509 CADILLAC Possible Causes

  • Faulty Idle Air Control (IAC)
  • Idle Air Control Valve harness is open or shorted
  • Idle Air Control Valve circuit poor electrical connection

How is the P1509 CADILLAC 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 P1509 CADILLAC code

Labor: 1.0

The cost to diagnose the P1509 CADILLAC 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)
  • Engine rough idle

P1509 CADILLAC Meaning

With the engine runtime 2 minutes, closed throttle, Engine Coolant Temperature (ECT) input over 122°F, Intake Air Temperature (IAT) over 62°F, VSS under 3 mph, the Powertrain Control Module (PCM) detects that the Actual idle speed was 175 rpm higher than desired idle speed.

More Information

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