The OBD code P1604 for Toyota indicates a malfunction in the Engine Control Module (ECM).
Symptoms include the Engine Light being ON.
Causes may include low battery charge, starting system issues, lowquality fuel, or a clogged fuel filter.
The problem is not severe but should be addressed.
A possible fix is to inspect the wiring harness, connectors, and components for damage or corrosion.
| Repair Importance Level | 10.0 (Out of 10) |
| Estimated Repair Time | Approximately 1.0 hour |
| Repair Difficulty Level | 10.0 (Out of 10) |
Symptoms of the Toyota p1604 OBD Code
The vehicle may experience intermittent starting issues or stalling with fault code Toyota P1604.
- Symptoms: Engine Light ON.
- Possible intermittent starting issues.
- Rough idle at startup.
- Engine stalling while driving.
- Difficulty accelerating smoothly.
Causes of the Toyota p1604 OBD Code
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Possible triggers for Toyota fault code P1604 include issues with the startability of the engine.
- P1604 can be caused by a faulty throttle position sensor.
- A broken wiring harness.
- Low voltage in the system.
- Corroded ground connections.
- Or signal loss between the ECM and the throttle actuator.
Fixing Toyota Error Code p1604 Step By Step
Address the issue by checking and repairing the internal control module communication error (Toyota P1604).
- To fix Toyota OBDII code P1604, first, review the possible causes mentioned above.
- Visually examine the wiring harness and connectors related to the ECM.
- Check for any damaged components and inspect the connector pins for signs of being broken, bent, pushed out, or corroded.
- If no issues are found with the wiring and connectors, consider reprogramming or replacing the ECM as necessary.
Cost Of Fixing Toyota p1604 Fault Code
The repair for Toyota fault code P1604 typically involves replacing the ECM.
The cost to diagnose and fix a Toyota OBD code P1604 typically ranges from $75 to $150, based on a 1. 0hour repair time.
Factors like shop rates and complexity can affect the final cost.
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Details of the Toyota p1604 OBD Code
The fault code P1604 in a Toyota indicates a communication error with the ECM.
Code P1604 for Toyota vehicles indicates a malfunction in the startability of the engine control module (ECM).
This code is triggered when the ECM detects an issue with the start signal circuit.
The start signal circuit is responsible for informing the ECM when the engine is being cranked or started.
If the ECM does not receive the proper signal indicating the engine is being cranked, it will set code P1604. This code is commonly associated with issues related to the ignition switch, wiring harness, or the ECM itself.
Mechanic’s Tech Notes
For Toyota fault code P1604, check for issues with the startability of the engine.
To diagnose and fix OBDII code P1604 in a Toyota, start by checking the Transmission Control Module (TCM) power and ground using a multimeter.
Verify TCM communication over the Controller Area Network (CAN) using a scan tool.
If the TCM does not respond, reprogramming or reflashing may be necessary.
Additionally, visually inspect the wiring harness and connectors for any damage, and check connector pins for signs of being broken, bent, pushed out, or corroded.
This thorough inspection will help identify and address the root cause of the P1604 fault code.
FAQ
Common symptoms of OBD code P1604 in a Toyota: Engine Light ON, possible causes include low battery charge, starting system issues, lowquality fuel, clogged fuel filter, or faulty ECM.
Possible causes of OBD code P1604 in a Toyota: Low battery charge, starting system issues, lowquality fuel, clogged fuel filter, or a faulty Engine Control Module (ECM).
Diagnose and fix OBD code P1604 in a Toyota: Symptoms Engine Light ON. Causes Low Battery charge, Starting system, Low quality fuel, Clogged Fuel filter, Faulty ECM. Fix Inspect wiring and connectors for damage.
Wrap Up
If your Toyota triggers OBDII code P1604, you may experience rough idling, stalling, or difficulty starting.
This code typically indicates an issue with the startability of the engine, possibly caused by a faulty starter relay, ignition switch, or wiring problem in the starting circuit.
To address Toyota OBDII code P1604, start by checking the starter relay and ignition switch for proper operation.
Inspect the wiring harness and connectors for any signs of damage, corrosion, or loose connections.
Replace any faulty components and ensure all connections are secure to resolve the issue effectively.
