Okay so Ive got and 01 Maxima GLE with new Vehicle Speed Sensor and Output Revolution sensor. Harness is fine and when the Transmission Control Unit is put into output mode I get 1 long and 11 short flashes of the O/D off light. Previously the third flash (after the initial long flash) was a long one but that was corrected by performing the idle air relearn procedure. Im thinking Ive got a bad TCU but Im not sure if I need the part labeled C1 or C2. Ive found them both for about 30 bucks and plan to install it myself just dont want to purchase the wrong one. Can anybody tell me for sure which is correct or how to identify it myself?

P.S. Just realized I never actually stated why I'm thinking that the TCU is bad... The speedo & odometers aren't working, and I'm experiencing the split second mis-shifts that feel like the car has gone into neutral momentarily. She happens to be my daily driver and I'm really hoping I can get things straightened out before much much worse happens. Worst come to worst I suppose I could take the thing apart and find out that way, but some input from somebody else could save me some headache.