Repair 7

Many motor vehicle accidents occur because other drivers and pedestrians dont see other vehicles until its too late. The daytime running lamp system on a 2004 Toyota Corolla turns on the headlamps at a reduced brightness level whenever the engine is running in order to combat this problem. This system helps other drivers and pedestrians to see the vehicle, reducing the likelihood of accidents and other potentially dangerous situations. In order to service the daytime running lamp system and make certain repairs, the daytime running lamp relay must be disconnected from the engines wiring harness.

Instructions

1

Turn off the engine and apply the Corollas parking brake. Shine a work light under dashboard, near the upper-right pedal area.

2

Locate the daytime running lamp relay; it is mounted on the right side of the foot well area. It is attached to the right under-dashboard wall, adjacent to the gas pedal. It is a small, square black relay and is third in a row of relays, furthest from the firewall.

3

Lift the locking tab on the relays connector with a small flat-head screwdriver and remove the relays electrical connector.

4

Start the engine and confirm that the daytime running lamps do not turn on. When youre done with your testing or repair, reconnect the daytime running lamp relays electrical connector and confirm that the lamps operate properly.

Correct ignition timing specifications are crucial for engine performance. Timing affects many variables, including fuel economy and engine longevity. Corolla is one of the most popular compact cars that was first introduced in 1966 and produced by Japanese automaker Toyota. Its engineers have determined precise timing specifications so that you can benefit from your Corolla as much as possible.

Measuring Ignition Timing

Use a timing light to check your timing while the engine is running. An inductive trigger signal will be picked up from one of the spark plug cables, causing the light to turn on and freeze while the spark plug fires. This helps to determine the crankshaft position. Use this information for making timing adjustments because the rate at which the crankshaft is spinning and is processed by the distributor controls the ignition (that is, controls when the spark should occur).

Timing Specifications

Ideally, the time at which the mixture should be fully burned on a Toyota Corolla is approximately 10 degrees before top dead center (BTDC) at 700 rpm.

Notes

Maximum RPM is not allowed. Cooling fan and vacuum advance (if equipped) should be turned off while adjusting the ignition timing.

You can clear the error codes on your Toyota Corolla right from your home garage, saving yourself time and money. Corollas made in 1996 or later come standard with an On-Board Diagnostics II computer (OBD II), whereas earlier Corollas come with an OBD I computer. You will need to purchase or borrow an OBD I or II scanner to read and clear the error codes. Sensors are positioned throughout the Corolla that detect malfunctions and send this information in the form of error codes to the computer, which in turn illuminates a warning light on the instrument panel. The sensors also keep track of the regular maintenance needs of the car, and this is displayed on the instrument panel in the form of a service light. Do not attempt to clear the error codes until you have had the vehicle serviced or repaired. The lights will keep turning themselves on if you prematurely reset the computer.

Instructions

1

Plug the scanner into the Diagnostic Link Connector (DLC) on the lower part of the drivers side dashboard near the hood release.

2

Put the key into the ignition, and turn it to the "on" position. Dont crank the engine. The scanner will turn on automatically.

3

Locate a command on the scanner that says "Erase Codes" or something similar. Select this command. Once the scanner has completed the task, it will display "Command Sent" or just return you to the main menu.

4

Unplug the scanner, and start the engine. Verify on the instrument cluster that all warning and service lights have shut off.