OK, i get 12 volts from the wire, but when i hook it up, voltage drops to around 4. Is this the relay sensing a closed circuit and misfunctioning? According to my voltmeter, the heater has a resistance of 18 ohms. Is that normal?
(i was asleep the day we did resistance in physics)
Also, adressing the choke light being on all the time. From wiring diagrams and your advice, i have determined that the choke heater relay is probably to blame. But.... where is it? (normally, mine might have been removed, explaining why i can't find it) and what are some ways to test it. Could it be responsible for both issues? How much do new ones cost?

Any help would be great
Thanks guys.

Choke relay is in the "convenience center" under the dash, above the gas pedal and right behind the ALDL connector.

18 ohms seems reasonable.

No idea what the relay costs, I'd expect $15 or so.

The Choke light is also the Alternator light (don't let me get started on that, or on the poor naming of the "convenience center") so the first question is, does your battery stay charged? if not, you need to start by replacing your alternator.

yea, my battery stays charged, thanks, i'll try and find it tomorrow in the light of day

RB83L69,
Is the choke relay the same type as the fuel pump relay?
If it is you can go to a freightliner dealership (or any big truck dealer) and get those relays for less than 5 bucks. the last relay I bought, I paid like 3 dollars for it. The same relay was 9.99 at a local autoparts store.