Here's what the book says:
http://www.sea-doo.net/SHOPMANUALS/PWC/2004/smr_2004_lineup_a.pdf
Page 603
I've hade to replace my information center due to corrosion; water got inside.
Information Center
4-TEC Models
When there is no display at the information center, perform the following:
– B.U.D.S. can be used to check its operation.
Look in the Monitoring tab.
– Check fuses.
– Check supply wire (1-23) and ground wire (1-8)
from MPEM.
– Check communication link wires (WHITE/RED
and WHITE/BLACK):
• To quickly check if the communication link is working, temporarily disconnect a sensor on the
engine to create a fault code. Start the engine. The information center should dis- play a fault
code when in onboard diagnostic mode.
• Check if wires are swapped, unconnected or short circuit.
• One faulty wire will cause a longer delay to perform the self-test when safety lanyard is
installed.
– If everything tests good, try a new information
center.