1996 Johnson/Evinrude Outboards 8 thru 15 Four-Stroke Service Manual, Page 270Get this manual
WATER TEMP Circuit 1Separate the connector between the engine harness and the temperature switch []
2Using jumper wire, connect the engine harness tan lead to clean engine ground3Turn the key switch to ON positionAfter the normal self-test sequence, the gauge WATER TEMP light should stay on If WATER TEMP light is not on, troubleshoot tan circuit for an open in the engine harness or the instrument harness4On engines, test both temperature switch tan circuits