Pro-150 Fault Finding Guide

We’ve written this guide to help customers diagnose and fix problems that may occur with the Pro-150.

Start by checking that the fuse tracks are intact, the location of these is shown in the manual.

The Pro-150 has a number of fault codes that can provide information about what the controller is reporting, these are listed in the manual.

If the fault codes don’t identify the problem, the next thing to do is to print out this troubleshooting voltage table, and then measure the voltages indicated. We have this video that shows how to do it.

There is further detailed information on the causes of some of the fault codes below.

The power up sequence is that the 12v PSU is fed initially via D9, this feeds the 5v supply which powers the processor. Once the processor is running it senses the ignition switch state, then does a number of self-tests which include charging and discharging the main capacitors using the relays, and also checking for mosfets faults. If the self-tests are passed, relay RL4 operates which connects B+ through to the motor terminals, mosfets, and direction relays. The following diagrams show the circuit diagrams and the physical locations of the relevant sections.

 

 

Fault code 05

Causes of fault code 05 that are internal to the controller are:

One or more main mosfets are short circuit. Measure the resistance between points A & B, then B & C in the picture. Expected values are 2MΩ – 4MΩ, damaged mosfets will show as 1Ω – 30Ω. If the mosfets are blown also check the 10Ω gate drive resistors. Short circuit mosftets can also cause the pre-charge resistors to burn, particularly at 48v.

Check the black plastic washers at D are present, these insulate the heatsink from the PCB.

Measure pre-charge resistance as shown. Check that Q16 is not short circuit.

This fault can also occur if the main power relay contacts RL4 have been damaged by long periods of operation at high current.

 

The relay driver transistors can be checked by measuring the resistance between B- and the points labelled E above [should be >1M].

To check the relay contacts measure the resistances shown in this table…

Fault code 04

One of the causes of this fault code is that the main relay contacts get welded together, usually by excessive current being drawn. This can be checked by measuring the resistance between the points circled red below, anything below approx 1k indicates welded contacts.

Pot faults

There is a very thin track on the PCB adjacent to the 3 and 6 way connectors, it’s circled in red in the picture below. This is actually a scratch through link that allows modifications to the input circuit, but under certain short circuit conditions we have seen this act as a 3rd fuse track and blow.

It’s easier to test this by measuring the resistance between the points indicated by the blue arrows. If there is no conductivity between these points, you can bridge them with some thin wire.