1994 Ranger RABS questions...
Blue Bowtie
08-07-2007, 10:36 PM
Generating a Code 12 - Low fluid level fault.
Master cylinder float switch appears to be closing both contacts on drop, opening both contacts on rise. I'm guessing that's as it should be.
Where is this elusive diode/resistor network located? The manuals indicate it is 3" to the left of the instrument cluster harness breakouts. I've got the cluster out, looking at the harness, and don't see even a discrete diode or resistor anywhere, let alone a "module" in that area. The tan wire from the M/C level switch to the RABS module is NOT grounded (like the Aerostars were notorious for) yet I cannot clear the Code 12. I suspect the "diode resistor module" is inadvertently signaling the RABS as a low M/C level, despite the switch being open. The red BRAKE warning lamp operates normally on start and with the application of the park brake, and all exterior brake lamps are functioning. The schematic isn't a lot of good if I can't find the components shown there in black and white.
Thanks in advance for any help or insights.
Master cylinder float switch appears to be closing both contacts on drop, opening both contacts on rise. I'm guessing that's as it should be.
Where is this elusive diode/resistor network located? The manuals indicate it is 3" to the left of the instrument cluster harness breakouts. I've got the cluster out, looking at the harness, and don't see even a discrete diode or resistor anywhere, let alone a "module" in that area. The tan wire from the M/C level switch to the RABS module is NOT grounded (like the Aerostars were notorious for) yet I cannot clear the Code 12. I suspect the "diode resistor module" is inadvertently signaling the RABS as a low M/C level, despite the switch being open. The red BRAKE warning lamp operates normally on start and with the application of the park brake, and all exterior brake lamps are functioning. The schematic isn't a lot of good if I can't find the components shown there in black and white.
Thanks in advance for any help or insights.
Blue Bowtie
08-09-2007, 09:41 AM
Just an update.
Don't feel bad if you were stumped by this one. I finally got a Ford tech involved, we poured over the schematics and pictorials, got more confused by the moment, and ended up calling the Ford factory help line. Evidently, despite what the schematic indicated, the "diode/resistor element" does not exist in some vehicles, even though the schematic is supposedly specific to the Ranger. The factory help line engineer suggested we JUMPER the harness at the ECBM (RABS module) to get the signals we need. Some "help" there, eh?
Don't feel bad if you were stumped by this one. I finally got a Ford tech involved, we poured over the schematics and pictorials, got more confused by the moment, and ended up calling the Ford factory help line. Evidently, despite what the schematic indicated, the "diode/resistor element" does not exist in some vehicles, even though the schematic is supposedly specific to the Ranger. The factory help line engineer suggested we JUMPER the harness at the ECBM (RABS module) to get the signals we need. Some "help" there, eh?
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