When you see the dreaded Honda code P1684, it can be a challenging problem to diagnose and fix. It is a Throttle Valve Return Spring Performance Problem, and it typically occurs when the ignition switch is in the LOCK (0) position, the coolant temperature is at least 158 ºF (70 ºC), and the battery voltage is at least 6 volts. There are also certain DTCs (diagnostic trouble codes) that must not be active for this issue to occur.
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The throttle valve opening angle must be 17 º or more, or 11 º or less, for at least 3 seconds. It is essential to record all freeze data and any on-board snapshots before troubleshooting the issue. The most common causes for Honda code P1684 are poor connections or loose terminals at the throttle body and the PCM or a faulty throttle body. With good troubleshooting and the right tools, you can easily fix this problem.
Causes and Solutions of Honda Code P1684
| Causes | Solutions |
|---|---|
| Poor connections or loose terminals at the throttle body and the PCM | Check connectors and terminals and fix or replace if necessary |
| Faulty throttle body | Replace the throttle body |
| Ignition switch LOCK (0) | Adjust the switch accordingly |
| Coolant temperature minimum 158 ºF (70 ºC) | Check the coolant level and replace if necessary |
Checking Connectors and Terminals
When diagnosing the Honda code P1684, the first step is to check the PCM and throttle body connectors and terminals. Inspect the connectors and terminals for any corrosion or damage. If any damage occurs, the terminals and connectors must be replaced. Ensure the connectors are properly secured, and all terminals are properly tightened.
Replacing the Throttle Body
If the connectors and terminals are in good condition, the next step is replacing the throttle body. When replacing the throttle body, it is essential to use a high-quality replacement part that meets the original equipment specifications. Ensure the throttle body is properly secured and connected to the PCM.
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Adjusting the Ignition Switch
If the throttle body has been replaced, the next step is adjusting the ignition switch. The ignition switch must be in the LOCK (0) position for the Honda code P1684 to occur. Make sure that the button is properly adjusted and that it is not in the wrong place.
Checking the Coolant Level
The last step is to check the coolant level. The coolant temperature must be at least 158 ºF (70 ºC) for the Honda code P1684 to occur. Check the coolant level and make sure that it is full. If the coolant level is low, then the coolant must be replaced.
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Conclusion
The Honda code P1684 is a Throttle Valve Return Spring Performance Problem that can be difficult to diagnose and fix. Following the steps outlined in this article ensures that the issue is correctly diagnosed and fixed. The most common causes of Honda code P1684 are poor connections or loose terminals at the throttle body and the PCM or a faulty throttle body. With the right tools and good troubleshooting, you can easily fix this problem.