🚨 Diagnostic Profile
Vehicle Make: Chrysler
Description: Throttle Actuator Control (TAC) Module Throttle Actuator Position Performance fault. This condition indicates the Powertrain Control Module (PCM) has detected that the electronic throttle body actual position does not correspond to the commanded position, which may result in reduced engine performance, rough idle, or a limp-home mode.
Diagnostic Trouble Code Reference: P2101 (Throttle Actuator Control Motor Circuit Range/Performance)
🚨 Repair Difficulty Tier
Tier: Intermediate
Throttle body inspection and cleaning is generally accessible, but verification requires scan tool live data, electrical testing, and possible throttle body relearn procedures. Component replacement may require programming or relearn using manufacturer-specific software such as a factory-level scan tool.
🛠️ Resolution Steps
Step 1: Preliminary Inspection
- Verify battery voltage is at a stable 12.4V-12.6V key-off and confirm charging system output is within the normal 13.5V-14.7V range at idle, as low or unstable voltage can cause false TAC performance faults.
- Inspect throttle body housing, bore, and blade for carbon buildup, oily residue from PCV/EVAP flow, debris, or physical damage that could cause binding or restricted blade travel.
- Check throttle body electrical connector for corrosion, bent pins, or loose seating directly at the throttle body housing connector; also inspect the main engine harness connector at the PCM for pushed-back pins or moisture intrusion.
- Inspect air intake ducting and clamps for leaks, cracks, or loose connections between the air filter housing and throttle body inlet, as unmetered air can skew throttle correlation logic.
- Check the accelerator pedal position (APP) sensor connector and wiring for chafing, pinching, or damage at the pedal assembly under the dash, since APP correlation faults often accompany TAC performance codes.
- Review freeze frame data and record DTC history using a compatible scan tool capable of reading enhanced Chrysler PCM data streams.
Step 2: Diagnostic Verification
- Monitor throttle actuator commanded position versus actual position using live bi-directional scan tool data; both throttle position sensor traces should move smoothly and in correlation with no more than a few percent deviation through the entire sweep.
- Perform a wiggle test on the throttle body harness and connector while monitoring live data for intermittent position dropout, voltage spikes, or DTC status changes.
- Verify ground circuit integrity at the throttle body and PCM chassis ground points using a digital multimeter, checking for less than 0.2V drop between the ground pin and a known good chassis ground with the circuit under load.
- Check the 5V reference voltage supply to the throttle position sensors using a digital multimeter backprobing the connector, confirming a stable reference signal (typically 5V ±0.1V) with the key on, engine off.
- Confirm whether the fault is intermittent or constant and whether it sets under specific load, throttle transition, or temperature conditions by data-logging a test drive.
- Check for related DTCs in the PCM, TCM, and ABS/ESC modules that may indicate a shared power, ground, or CAN communication fault affecting throttle correlation logic.
Step 3: Resolution & Reset Process
- Clean the throttle body bore and blade using an approved throttle body/intake cleaner labeled safe for electronic throttle bodies, avoiding aerosol contact with the throttle position sensor itself.
- Repair or replace damaged wiring, connectors, or terminals as needed, applying dielectric grease to all reconnected electrical joints to prevent future corrosion.
- If throttle body replacement is required, install the new unit and perform the required throttle body/idle relearn procedure using a capable scan tool, as Chrysler TAC systems typically require this relearn to reset minimum airflow and closed-throttle position values.
- Clear DTCs and perform a full drive cycle road test, including idle, cruise, and wide-open throttle acceleration, to confirm the fault does not return.
- Verify idle quality, throttle response, and absence of limp-home (reduced power) mode after the reset, and re-scan to confirm no pending or stored codes remain.
📦 Parts, Labor, and Budget Estimates
Required Components/Software: OEM or OE-quality electronic throttle body assembly (if replacement is needed), throttle body/intake cleaner safe for electronic throttle systems, electrical contact cleaner, dielectric grease, replacement connector pigtail or terminals (if damaged), and a capable scan tool with bi-directional control and relearn/idle reset functionality (factory-level tool strongly recommended for full relearn access).
Average Component Price: $150-$450 for a new OEM or OE-quality electronic throttle body assembly depending on model and year; $10-$25 for throttle body cleaner and electrical contact cleaner; $5-$20 for dielectric grease and minor connector hardware; $0-$150 for dealer or independent shop diagnostic software access if a factory-level relearn procedure is required and not already available in-house.
Estimated Labor Hours: 0.5-1.0 shop book hour for initial diagnosis, wiring/connector inspection, and throttle body cleaning; an additional 0.5-1.0 shop book hour if full throttle body replacement and relearn procedure are required, for a combined total of approximately 1.0-2.0 shop book hours depending on accessibility and whether electrical repairs are also necessary.