dependable
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A truck I am fixing (M1010 with 1008 wire harness both cab and engine) has wiper problems. Looked at TMs, used search and have been under the hood a couple hours.
Blows fuses when wiper on low, works on high. Washer does not try to engage. Have tried a couple different wiper motors. Noise suppression capacitors bypassed and contacts clean. Wiper fuse blows in low even with fuel heater disconnected.
Does any one know a test procedure for wiper switch? Too time consuming to swap out as a diagnostic.
Discovered that when wiper switch is disconnected, wiper motor goes on when fuel heater plugged in(with ignition on). Getting 12.3 v to fuel heater and am aware it is fed by same fuse, but think that is kind of weird. Fuel heater tests at 2 ohms. Fuel heater on NOS filter base tests at 2.3 ohms, is that enough difference to indicate a short? Fuse blows even with heater unplugged.
I guess it may be time to dissect wire harness again, but a multi meter test procedure for switch would be helpful, as I did test harness before I installed it. The 1010 harness was compromised by duvac meltdown for previous owner.
This truck has been a back burner project for a couple of years because of problems like this. Thanks.
Blows fuses when wiper on low, works on high. Washer does not try to engage. Have tried a couple different wiper motors. Noise suppression capacitors bypassed and contacts clean. Wiper fuse blows in low even with fuel heater disconnected.
Does any one know a test procedure for wiper switch? Too time consuming to swap out as a diagnostic.
Discovered that when wiper switch is disconnected, wiper motor goes on when fuel heater plugged in(with ignition on). Getting 12.3 v to fuel heater and am aware it is fed by same fuse, but think that is kind of weird. Fuel heater tests at 2 ohms. Fuel heater on NOS filter base tests at 2.3 ohms, is that enough difference to indicate a short? Fuse blows even with heater unplugged.
I guess it may be time to dissect wire harness again, but a multi meter test procedure for switch would be helpful, as I did test harness before I installed it. The 1010 harness was compromised by duvac meltdown for previous owner.
This truck has been a back burner project for a couple of years because of problems like this. Thanks.