Gauge Issue
The gauges on our 2001 Itasca Horizon have been erratic. Oil pressure, speedometer and tach were not working properly. Took to Local Freightliner dealer (thinking a ground issue was the culprit), wh...
Forum Discussion
I HAD A SIMILAR PROBLEM ON A 96 GM CHASSIS. THE SPEEDOMETER OPERATES ON AC CURRENT PRODUCED BY A SMALL AC DEVICE ON THE TRANSMISSION.IF THE DIODE IS BAD ON THE BELT DRIVEN ALTERNATER ON THE FRONT OF THE ENGINE A SMALL LEAKAGE OF AC VOLTAGE WILL GO THRU THE ELECTRICAL SYSTEM WHICH WILL CAUSE THE SPEEDOMETER TO REACT.THERE SHOULD BE NO AC VOLTAGE COMING OUT OF THE ALTERNATER WHEN THE ENGINE IS RUNNING. AN ELECTICAL TOOL LIKE A FLUKE SHOULD BE USED TO DIAGNOSIS.SET THE FLUKE TO AC VOLTAGE, PUT ONE WIRE TO GROUND AND THE OTHER WIRE ON THE OUTPUT WIRE, THERE SHOULD BE A ZERO READING IF EVERYTHING IS OK. ANY READING WOULD INDICATE A BAD DIODE IN THE ALTERNATER. GOOD LUCK
