Curtis 3501 Manual -

This is often a throttle signal noise issue. The Curtis 3501 manual suggests adding a 10k ohm resistor across the throttle wiper and low pins. This "pull-down" resistor stabilizes the input. The exact value and wiring diagram are only in the official documentation.

The Curtis 3501 can accept various throttle inputs: 0-5k ohm, 5k-0 ohm, 0-5V, or even a single-ended potentiometer. The manual contains a or programming sequence to set the correct throttle type. If your vehicle runs full speed as soon as you turn the key, you have a throttle mismatch error—fixable only via the manual’s calibration procedure. curtis 3501 manual

Uses a standard 16-pin TYCO Mini Universal Mate-N-Lok connection matrix. This is often a throttle signal noise issue