A no-crank condition when hot usually points to issues with:
* Starter: The starter motor itself could be failing, especially when hot. The internal components might expand and lose contact, preventing engagement.
* Starter Solenoid: This is the electromagnet that activates the starter. Heat can cause issues here as well.
* Battery/Cables: A weak battery or corroded/loose battery cables can struggle to provide enough current when hot.
* Ignition Switch: A failing ignition switch might not be supplying power to the starter circuit consistently, particularly when hot.
* Neutral Safety Switch: Prevents starting unless the transmission is in Park or Neutral. A problem here could be heat related.
While a severely malfunctioning TPS *could* indirectly contribute to a no-crank scenario by causing a strange signal that interferes with other systems, it's not the typical cause. A bad TPS is more likely to cause drivability problems like stalling, rough running, or poor fuel economy.
Troubleshooting Steps:
1. Check the obvious: Battery voltage, cable connections, and the condition of the starter.
2. Test the starter: Have it load tested to check for its ability to engage.
3. Check the starter solenoid: See if it's clicking.
4. Inspect the ignition switch: Look for any signs of damage or wear.
5. Neutral safety switch: Check that the transmission is in Park or Neutral.
Only after ruling out these more common causes should you investigate the TPS. You can test the TPS's voltage output with a multimeter, but that's a more advanced diagnostic step. A bad TPS would likely present other symptoms before preventing starting.
