Code
P2100
Generic
P — Powertrain
Throttle Actuator A Control Motor Circuit/Open
Views:
UK: 39
EN: 77
RU: 71
AI status
Completed
Completed
100%
Causes
- Open or damaged wiring harness to throttle actuator motor
- Corroded, loose, or damaged connector at throttle body or ECM
- Failed throttle actuator (motor) or internal motor windings open
- Blown fuse or failed relay supplying throttle motor power
- Faulty ECM/PCM driver circuitry
- Poor or missing ground at throttle body/ECM
Symptoms
- Check Engine Light (MIL) on
- Reduced engine power / limp mode
- Poor throttle response, hesitation, or no response to accelerator
- Engine may stall or idle poorly in some conditions
- Stored or recurring DTC P2100 (may occur with related ETC codes)
What to check
- Read and record all stored DTCs and freeze frame data; note conditions when DTC set
- Visually inspect throttle body connector and harness for damage, corrosion, or water ingress
- Check related fuses and relays for continuity and proper operation
- Perform wiggle test on harness with key ON (engine off) while monitoring for voltage/continuity changes
- Measure supply voltage and ground at throttle actuator connector with connector connected
- Check continuity between throttle actuator terminals and ECM connector pins (with ignition OFF)
Signal parameters
- Supply voltage at throttle actuator power feed: approximately battery voltage (~11–14 V with ignition ON) — verify per vehicle
- Motor winding resistance: typically low ohms (single-digit to tens of ohms) depending on design — consult service spec
- Control signals: ECM commonly uses H-bridge or PWM to drive motor; PWM frequency and duty vary by manufacturer
- Expected continuity between motor terminals and ECM pins when harness intact (near 0 ohms to specified winding resistance)
- No continuity (open) indicates wiring break or open motor coil
Diagnostic algorithm
- Verify the code: connect a scan tool, confirm P2100 is active or historic, note freeze frame conditions.
- Check fuses/relays: inspect and test any fuse or relay that supplies the throttle body motor circuit; replace if blown or faulty.
- Visual inspection: examine connectors, pins, and harness for corrosion, bent pins, breaks, or water intrusion; repair as needed.
- Measure voltage/ground: with ignition ON (engine OFF), measure battery voltage at the throttle actuator power terminal and check for a solid ground at ground terminal.
- Check continuity: with ignition OFF and battery disconnected if required by manufacturer, measure continuity between throttle actuator motor terminals and ECM connector pins. Look for opens or high resistance.
- Measure motor resistance: if allowable, measure resistance across motor windings and compare to spec. An open winding indicates actuator replacement.
- Backprobe while operating: if safe and per procedure, backprobe motor control terminals while commanding throttle movements to observe PWM or driver outputs with a scope or lab meter.
- Isolate circuit: if open in harness, repair wiring/connector. If harness is good but no driver output from ECM, suspect ECM driver failure and confirm with manufacturer diagnostics before replacement.
- Clear codes and test drive: after repair, clear DTCs and verify the fault does not return and throttle relearn procedures are completed if required.
- If replacement of throttle body or ECM required, follow calibration/relearn procedures specified by manufacturer.
Likely causes
- Open or broken wire between ECM and throttle actuator
- Damaged/contaminated connector at throttle body
- Failed throttle actuator motor (open winding)
- Blown fuse or poor ground
- ECM output driver failure (less common)
Fault status
Status
Throttle Actuator A Control Motor Circuit/Open — Open circuit detected in throttle actuator control motor wiring or motor. ECM may limit engine power until condition is resolved.
Repair difficulty: Medium
Diagnostic time: 0.5-2.0 hours
Similar codes
Your experience will help others
+100 karma for a short comment :)
Was this AI description helpful?
Your feedback helps improve AI descriptions.
👍 Like
0
👎 Dislike
0
Send to email