Dash brake light not working

1990 Limited, factory abs which I converted to non abs. (Dual diaphragm booster/master cyl) So, when I pull the park brake, no light on the dash. Turn the key to run position, no dash brake light. Crank the engine and the light comes on while cranking, turns off as soon as it starts. So the bulb is working. Checked the park brake switch and it’s functioning as intended (goes to ground with the lever pulled). All fuses check out. All the abs components have been removed, however the wiring is still there, just unplugged. Is there a wire or something in the abs harness that needs to be connected or grounded to make my park brake indicator work properly? I have an explorer 8.8 and every time I get the park brake working right, I drive with it engaged and then it throws off all my adjustments! Very frustrating

There are brake light wiring differences between the ABS and non-ABS. Do you have +12volts at the parking brake switch connector? Head over to Cruiser54.com and checkout the wiring diagrams in the FSMs.

The parking brake switch is a grounding switch. So no 12v there. I’ll check out Cruisers site again for the diagrams. Musta missed those last time. Thanks.

Baddad said:

The parking brake switch is a grounding switch. So no 12v there. I’ll check out Cruisers site again for the diagrams. Musta missed those last time. Thanks.

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Yup, it's providing the ground for the bulb in the dash. Measuring with a voltmeter, you should see 12v across the switch when the parking brake isn't engaged. If you don't then I'd suspect wiring from the p-brake switch to the bulb, as the bulb seems to have +12volts already if it lights up when starting.

Ah, I see what your saying. I’ll check that tomorrow. Thanks

Boxbum over on Cherokee Forum posted this and it worked like a charm!

The circuit is powered by a feed in the light cluster. As it comes on while cranking, it means there is power to the bulb.

That just took me a while to trace back and properly work out so I'm 99% sure on this, the ABS module does play a part in this. The parking brake switch runs to another brake switch then into the ABS module, a feed then comes back out which heads off to all of the other ground paths and the dash bulb.

Please test this out before jumping wires but you should find pin C9 (ABS module connector) will be grounded with the park brake switch engaged or the low fluid level switch engaged. Pin C5 should be +12V and when you crank it over, should drop to 0V as the light turns on. If this all checks out, by rights, jumping those 2 pins should complete the circuit and give you your dash light back. Let me stress, please test that what I have said matches up and if you have any doubts, don't be jumping wires across.