What Does P2104 Mean?
The PCM has commanded the throttle actuator to forced idle position due to detecting a fault in another system that requires engine power limitation. This is a safety response code, not a throttle system failure.
Safety Warning
Vehicle will only idle and not respond to accelerator input, making normal driving impossible. Do not attempt highway driving as vehicle cannot maintain speed or accelerate.
Common Causes
30%
Accelerator pedal position sensor failure or correlation error
25%
Throttle position sensor malfunction or out of range signal
20%
Critical transmission fault triggering torque reduction request
15%
ABS or traction control system requesting engine torque limitation
10%
PCM detecting critical engine fault requiring power reduction for protection
Diagnostic Steps
1
Step 1: Check for all other DTCs stored in PCM and other modules (ABS, TCM, BCM); prioritize diagnosing those codes as they likely triggered P2104
2
Step 2: Monitor accelerator pedal position sensor voltages with scan tool; verify smooth progression from 0-100% with no dropouts or erratic readings
3
Step 3: Check throttle position sensor signals for proper voltage range and correlation during idle and key-on engine-off conditions
4
Step 4: Review freeze frame data to identify driving conditions and other faults present when P2104 set
5
Step 5: Clear codes after addressing root cause faults and perform drive cycle to verify forced idle condition no longer activates
Estimated Repair Cost
$100 - $1,200
Parts + labor, varies by vehicle and location
The PCM has commanded the throttle actuator to forced idle position due to detecting a fault in another system that requires engine power limitation. This is a safety response code, not a throttle system failure.
The most common cause of P2104 (Throttle Actuator Control System - Forced Idle) is: Accelerator pedal position sensor failure or correlation error
Typical repair costs for P2104 range from $100 to $1,200, depending on the vehicle, location, and whether you do it yourself or go to a shop.
Vehicle will only idle and not respond to accelerator input, making normal driving impossible. Do not attempt highway driving as vehicle cannot maintain speed or accelerate.
Start by connecting an OBD2 scanner to read the code and any freeze frame data. Then follow the diagnostic steps specific to P2104 to identify the root cause.
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Quick Info
Category
Powertrain
System
Electronic Throttle Control System / Multi-System Fault
Difficulty
Type
Generic (SAE)
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