ABS light on, O/D light flashes! HELP
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ABS light on, O/D light flashes! HELP
I have a 94 E-350 with the 7.4 liter and E4OD trans.
The ABS light has been on forever and when I turn the key to the priming position I hear several clicks coming from the engine compartment and the voltage indicator dips with each click, but I've never noticed any issues with the brakes, it stops just fine. I got looking around underneath her and found the transmission control module had been melted badly by an exhaust pipe that was put in when I had a turbo installed several years ago. I unplugged the TCM and the ABS light went off and the clicking no longer occurs. I plugged in a replacement TCM and the ABS light & clicking is back. Also I had the rear end rebuild when I first got the bus. I've heard there is a gear in there that the ABS sensor reads. I've replaced the sensor, is it possible that that gear was left out or somehow damaged?
The other issue is the blinking O/D light. It does it at random times with nothing obvious triggering it. It's not throwing a code, it just blinks steadily and throws the transmission into limp mode. I've checked every light and fuse that I can find and I'm wondering if I need to just start tracing wires. We've made several modifications to this vehicle like TVs, neon lights, spot lights, CB radio, power inverters and a security system. I'm concerned that we've either caused some sort of short or maybe had a mouse chew into something.
The ABS light has been on forever and when I turn the key to the priming position I hear several clicks coming from the engine compartment and the voltage indicator dips with each click, but I've never noticed any issues with the brakes, it stops just fine. I got looking around underneath her and found the transmission control module had been melted badly by an exhaust pipe that was put in when I had a turbo installed several years ago. I unplugged the TCM and the ABS light went off and the clicking no longer occurs. I plugged in a replacement TCM and the ABS light & clicking is back. Also I had the rear end rebuild when I first got the bus. I've heard there is a gear in there that the ABS sensor reads. I've replaced the sensor, is it possible that that gear was left out or somehow damaged?
The other issue is the blinking O/D light. It does it at random times with nothing obvious triggering it. It's not throwing a code, it just blinks steadily and throws the transmission into limp mode. I've checked every light and fuse that I can find and I'm wondering if I need to just start tracing wires. We've made several modifications to this vehicle like TVs, neon lights, spot lights, CB radio, power inverters and a security system. I'm concerned that we've either caused some sort of short or maybe had a mouse chew into something.
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Joined: Jan 2005
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I assume this is a 7.3 IDI diesel. In which case the clicking and volt gauge flickering is normal. It is the glowplug relay cycling the glowplugs to improve cold running.
Can you clarify what you mean by the "TCM"? Usually this would refer to the transmission computer which, on your vehicle, should be under the dash, I would think.
Yes, there is a tone ring inside the axle housing from which the vehicle speed sensor gets its signal. This signal is used by the vehicle speedo, the RABS and the transmission. So I would think if your speedo is working correctly then the tone ring is good.
You are probably going to have to check the RABS computer for trouble codes to find that problem, although the system is poor anyway and a piece of tape over the light may be the best fix.
Can you clarify what you mean by the "TCM"? Usually this would refer to the transmission computer which, on your vehicle, should be under the dash, I would think.
Yes, there is a tone ring inside the axle housing from which the vehicle speed sensor gets its signal. This signal is used by the vehicle speedo, the RABS and the transmission. So I would think if your speedo is working correctly then the tone ring is good.
You are probably going to have to check the RABS computer for trouble codes to find that problem, although the system is poor anyway and a piece of tape over the light may be the best fix.
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Yeah, 7.3 liter. My bad.
The TCM looks just like the ECM under the dash but it's located on the frame near the transmission. I'm assuming it's a Transmission Control Module (or transmission computer/brain), am I wrong on that?
The TCM looks just like the ECM under the dash but it's located on the frame near the transmission. I'm assuming it's a Transmission Control Module (or transmission computer/brain), am I wrong on that?
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