AutoCodes – Cadillac – P1604 Cadillac

P1604 Cadillac Code - Loss Of IPC Serial Data Conditions

Quick Answer

With the engine running engine speed over 500 rpm for 10 continuous seconds, the Powertrain Control Module (PCM) detects an invalid serial data signal or no serial data from the Instrument Panel Cluster (IPC) to PCM for 11 seconds. Common causes include Faulty Instrument Panel Cluster (IPC), Instrument Panel Cluster harness is open or shorted, Instrument Panel Cluster circuit poor electrical connection. Severity is High - diagnose this code as soon as possible. Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.

What it means: P1604 Cadillac indicates Loss Of IPC Serial Data Conditions.
Common causes: Common causes include Faulty Instrument Panel Cluster (IPC), Instrument Panel Cluster harness is open or shorted, Instrument Panel Cluster circuit poor electrical connection.
Severity: High - diagnose this code as soon as possible.
Can I drive?: Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.

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Code Popularity 7,559

How popular is this code, among other codes? Low

Repair Importance Level

Urgent (Diagnose now) (3 / 3)

Repair Difficulty Level

Advanced (Pro) (3 / 3)

What is this?

Table of contents Created and updated by William Orellana on May 20, 2019

Description
Step-by-Step Diagnostic Guide
Possible Causes
How To Fix
Cost to Diagnose
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Code P1604 Cadillac Description

OBDII Code P1604 Cadillac - Loss Of IPC Serial Data Conditions - AutoCodes.com — P1604 Cadillac Code - Loss Of IPC Serial Data Conditions

What does this mean?

What are the Possible Causes of the DTC P1604 Cadillac?

Faulty Instrument Panel Cluster (IPC)
Instrument Panel Cluster harness is open or shorted
Instrument Panel Cluster circuit poor electrical connection

How to Fix the DTC P1604 Cadillac?

Review the 'Possible Causes' above and visually examine the corresponding wiring harness and connectors. Check for damaged components and inspect connector pins for signs of being broken, bent, pushed out, or corroded.

What is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the P1604 Cadillac code, it typically requires 1.0 hour of labor. Rates vary by location, vehicle, and shop. Many shops charge between $80–$150 per hour; dealerships and metro areas may be higher, independents may be lower.

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About the author: William Orellana is a Master Mechanic and Mechanical Engineer with over 30 years of experience diagnosing and repairing vehicles. Learn more about his background.