Reset check engine light 93 jeep - 1993 Jeep Grand Cherokee

93 ZJ 5.2L grand cherokee.

FSM real. USA.
http://www.jeep4x4center.com/knowledge-base/index.htm?utm_source=cj#service

click emissions
see page 25-3 for flash codes.. its there. for your jeep
the Diagnostic is activated by fast ignition key cycles ,stated there.
in 5seconds.

next slide down to wiring. in the window. above.
page 8w-40-4
CEL lamp' schematic pin C2-6 blk/LG color
see the trip switch, this is the silly leaded fuel trip timimer

best i can tell this jeep has the CCD buss
the CLuster is stand alone processor. it communicates
from PCM to the Display VIC. the VIC glows the lamps.
Or has the GDM display, there are 2 options.
BASE graphics display module or VIC option.
ah page 8e-4 tells you the CEL is not hardwired lamp.
it uses the fancy back light display.

so do the key flash trick so see the display show CEL flash codes.
my guess, all this is in the log lost operators guide too.

If the check engine light does not light up on the dash when you turn on the ignition, at those times when your jeep doesn't want to start, then your main jeep ecm is in need of repair. The fuel pump relay will get energized only after that check engine light comes on. It's a known problem, especially with the first and second year production Grand Cherokees, 93 and 94.

If the check engine light does NOT come on when cranking, at the times when it won't start, and the relays are clicking and buzzing, then your ECU is in need of repair. The engine will only start after the check engine light comes on and the ecu is what controls that. ECU is likely going bad, causing the delayed start problem typical of early 90's jeeps. Reasonably priced repair or replacement services for your jeep ECU are available on ebay.

If the check engine light does NOT come on when cranking, at the times when it won't start, and the relays are clicking and buzzing, then your ECU is in need of repair. The engine will only start after the check engine light comes on and the ecu is what controls that. ECU is likely going bad, causing the delayed start problem typical of early 90's jeeps. Reasonably priced repair or replacement services for your jeep ECU are available on ebay.

You may have a loose or dirty battery connection. Take of the cables and clean the battery lugs and the terminals. Make sure they are tight when you put them back. Check the connections on the starter as well as the ingnition comes from there. Disconnect the earth cable first and put it on last, this is to prevent heavy shorts that can cause some damage.

Your main ECU is in need of repair. Your jeep is displaying signs of the common delayed start problem. The check engine light does not light up, for a while, then when it finally does, the fuel pump gets power and it starts. Have your ecu repaired.

Your jeep is suffering from what is called the "delayed check engine light problem". Your main computer ecu is in need of repair. Some internal components, ones that normally send power to energize the various engine relays, have gone bad from age. Have the ecu repaired. That services is offered on ebay.

If the check engine light is not lighting up, on the dash, when you turn on the ignition, your ecu might be in need of repair.

If your check engine light does not come on, on the dashboard, when you turn the ignition on then your jeep ecu computer is in need of repair.

When the check engine lights turn on, I suggtes scabbed the PCM to know excatly what fault code in there. With this code number we can send additional details.

Check here to know how to read ENGINE CODES

Hope helps (remember to rate and comment this).