Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
SYS.OK|MANUAL.DB● LIVE
HOMESERVICE MANUALSCHEVROLET1987STEP VAN P20, 6.2 J, STANDARDREPAIR AND DIAGNOSIS (SINGLE PAGE)ENGINE PERFORMANCETESTING & DIAGNOSISCCC TBI TESTS W/CODESDIAGNOSTIC CHARTSA/C CLUTCH CONTROL DIAGNOSIS (2.8L)TEST DESCRIPTION
1987 Chevrolet Step Van P20, 6.2 J, Standard
Test Description
1987 Chevrolet Step Van P20, 6.2 J, StandardSECTION Test Description
NOTE:
Test numbers refer to test numbers on diagnostic chart.
- Checks for low refrigerant as cause for no A/C.
- This and following tests check for faulty A/C control relay.
- Checks for faulty cycling switch. Solenoids and relays are turned on and off by the ECM, using internal electronic switches (drivers). Each driver is part of a group of 4, called "Quad-Drivers". Failure of one driver can damage any other driver in set. Solenoid and relay coil resistance must measure more than 20 ohms. Less resistance will cause early failure of ECM driver. Using an ohmmeter, check coil resistance of A/C relay before replacing ECM.
RENDER: 1.0x
NO RELATED
Recommended Tools & Savings
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
Affiliate disclosure: We may earn a commission at no extra cost to you.
When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.