P1587 — Throttle Control Unit Modulated Command Malfunction

What Does P1587 Mean?

P1587 is a manufacturer-specific diagnostic trouble code: Throttle Control Unit Modulated Command Malfunction. This code applies to FORD, LINCOLN, MERCURY, OTHER, VOLKSWAGEN vehicles. Unlike generic OBD-II codes, manufacturer-specific codes are defined by the vehicle maker and may only apply to certain makes and models.

Symptoms of P1587

⚠️ Check Engine Light (MIL) illuminated
⚠️ Throttle Control Unit Modulated Command not operating correctly
⚠️ Related system in reduced functionality mode
⚠️ Reduced engine performance

Common Causes

🔍 Throttle Control Unit Modulated Command has failed or is degraded
🔍 Wiring or connector issue in Throttle Control Unit Modulated Command circuit
🔍 Related mechanical component affecting Throttle Control Unit Modulated Command
🔍 Software update needed for ECM/PCM

Frequently Asked Questions

What does P1587 mean?

P1587 indicates: Throttle Control Unit Modulated Command Malfunction. The vehicle's computer has detected that the Throttle Control Unit Modulated Command is not operating within its expected parameters and stored this diagnostic trouble code.

Can I drive with code P1587?

You can drive short distances for essential trips, but schedule a diagnosis soon. Driving with P1587 for extended periods may cause additional problems.

How much does it cost to fix P1587?

Repair costs for P1587 typically range from $80 to $300, depending on the root cause. Simple wiring or connector repairs are on the lower end, while component replacement costs more. A proper diagnosis ($80–$150 at most shops) will identify the exact cause before committing to expensive parts.

What To Do Next

Possible Fixes

🔧 Inspect Throttle Control Unit Modulated Command and related wiring
🔧 Replace faulty Throttle Control Unit Modulated Command

1
Find your vehicle above
Click your make and model for real owner reports and common causes specific to your vehicle.
2
Check for recalls
Go to nhtsa.gov/recalls and enter your VIN. Free repairs if covered.
3
Get a professional diagnosis
A code alone doesn't identify the exact failed part. A diagnostic ($50–$150) pinpoints the root cause.

P1587: Throttle Control Unit Modulated Command Malfunction