Apple Macbook Pro Aluminum 13-Inch Black Laptop Keyb Technical Guide - Page 40

6. Connect External video Yes Video correct on external Connect known-good VGA/ display. Research available DVI adapter to known-good firmware and software display, press power button updates, retest. and close display to force main screen startup on external If returning with software video. Verify that video is already updated, go to Step 7 correct when displayed from external display. No Replace logic board with according symptom code: -no video M03 -bad/distorted video M04 7. Isolate LCD display detection Disconnect external monitor and reopen display and restart unit. Verify that sleep LED indicator goes off after internal LCD has been detected. Yes Sleep LED goes off when LCD detected. -If still no video then Go to step 8, -If video present, but with defect, go to step 9 No Internal LCD not detected. Run Clamshell Service Diagnostic utility and check for LCD panel presence. If not found, reseat LVDS cable connection on logic board and retest. If sleep led does not go off after cable is reseated, go to step 10 8. Check for sleep sensor Yes Sleep sensor was stuck or had condition shorted cable. Replace IR/ X13 If display assembly sleep sleep cable (or enclosing top sensor is stuck in a closed state, case) video will appear on internal display temporarily, until the No Symptoms unchanged - Go OS sleeps the system. to Step 9 Disconnect IR/sleep cable and restart unit without external display. Verify that system starts up with video on internal display stays on and does not go into sleep mode. 2010-06-15 MacBook (13-inch, Aluminum, Late 2008) Symptom Charts - Startup and Power Issues 40