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.
Relay Control Module Test
The relay control module is part of the under-hood fuse/relay box, and it contains these relays:
- PGM-FI main relay 1
- Ignition coil relay
- PGM-FI subrelay
- ETCS control relay
- Horn relay
If any of these relays fail the test, replace the under-hood fuse/relay box.
- Do the battery terminal disconnection procedure (see
USING THE GR8 BATTERY DIAGNOSTIC STATION
), then disconnect under-hood fuse/relay box connectors C (2P), E (14P), and H (9P).NOTE: All connector views are wire side of female terminals.
Use the Manual With the Right Hardware
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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.
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