1991 Chevrolet Caprice 5.0L Automatic - ABS Lite Light Illuminates Occasionally

I'm trying to get my 1991 Chevrolet Caprice with a 5.0L engine and automatic transmission back into service by Friday. The vehicle has been parked since 2015 and originally had over 46,000 miles. It was previously owned by my parents before their passing. The ABS 'Lite' warning light comes on intermittently. I've already drained the old brake fluid from the reservoir using a turkey baster and refilled it with fresh brake fluid as recommended. I’ve been advised that jumping pins A and B in the ABS module can trigger code flashing, but the diagnostic chart I found does not list any ABS-related codes for this model. I'm seeking help to understand what might be causing the ABS lite issue and how to properly retrieve or interpret fault codes. Any insights or guidance would be greatly appreciated. Best regards, Wyr God bless