I have a 23 year old pitco fryer, an E 18s...

I have a 23 year old pitco fryer, an E 18ss. I cannot get the fryer to heat up. I think that it is something to do with the thermostat. I changed the module and it still won't heat.Any suggestions? I Also changed the relays. The elements will heat up in the test mode. I called pitco and they said that they never heard of there fryers having a test mode. What is the deal with that? When power is applied, the left relay engages. but the only time that the right one works is in the test mode! Thanks!