2002 Avalon XLS, ABS light and EFI relay

I think you have 2 separate problems. The flashing ABS light is telling you that the ABS portion of your braking system is inoperative. Since the problem occurs when the car is wet, I should suspect water in a speed sensor connector or near the ABS relay. A code scan will help point the technician to the trouble spot.

The EFI relay clicking may be caused by the ignition switch or by water near the junction block where the relay is located. If it is the same block as the ABS relay, I'd check it for water intrusion.

Thank you. This may be two separate problems, however, they have always occured together. If you are correct, then it is possible that the same area that gets wet affects both sensors. Can you tell me exactly where I should look for the water intrusion?

PS. Today the car ran normally with no ABS lights or relay clicking. I suspect the problem area has dried up and sensors are acting normal.

Look in the fuse box under the hood. Before you remove the cover, make sure it is on correctly and there are not cracks in the cover.

I have checked fuse box cover and integrity and it seems solid. I could find no evidence of leaks or even water marks in the area. Is there somewhere else that water could be getting in to cause these problems?

I have heard of others who had water getting in a cracked tail light lens and causing strange unrelated electrical anomolies, but I checked every light cover on the car, and they all looked clean and solid with no moisture inside. I checked the primary sources of water leaks (hood seam, light covers, trunk seam, wiper recess etc.), but could not find any evidence of leakage. There are some water marks on the firewall area, but those look like they came from splashing from the undercarriage area. Two of these incidents came after car washing only with no splashing from puddles etc.

Anyone have any ideas where I could look for possible causes? Any idea on what kind of short or leakage could cause these two unrelated problems? Possibly a wire bundle that got knicked somewhere? Possibly the leads to these either EFI or ABS sensors? Any further troubleshooting ideas would be appreciated. Thanks.

I am not aware of any widespread problems like you are describing. By any chance was the car ever in an accident? Are there any aftermarket accessories installed like a remote starter, fog lights, satellite radio, etc? If there is a yes to any of those questions, I'd start checking the areas where the factory wiring was disturbed. If no, then all I can suggest is to try wiggling wires and wire looms when the problem occurs or take it to a dealership for diagnosis.

Make sure tire wear is even and pressure in tires is same all around.

Stock XLS, nothing aftermarket added. Never in accident. Hit fairly deep pothole once is closest thing to collision. Four fairly new tires with air pressure normal. Did have a flat tire (nail), but problem occurred after that and after washing only.

I know this is a wild troubleshooting task. I also know this car's primary (maybe only one) weakness has been the electrical system. I have been trying to concentrate my efforts on finding out where moisture could affect either of these components. Can anyone tell me exactly where the ABS sensor is located? Exactly where does the EFI relay get it's input? That might help.

There are 4 ABS sensors, one for each wheel. Each hub has teeth that look like splines, and the sensor magnetically picks up the presence or absence of the spline as the hub rotates, creating an on-off signal. The faster the on-off signal, the faster the wheel is rotating, and if one wheel is rotating at a different speed when the brakes are applied, the ABS system kicks in. Look for a wire that snakes behind the brake backing plate, and follow the wire to the ABS sensor.

A flashing ABS light is different from one that is constantly illuminated, and I'd have to do some research to find out its significance.

The EFI relay probably gets its control voltage from the main computer.

You can get online access to the factory repair manual at techinfo.toyota.com for $10/day.

replying to erom43, Byron pierce wrote: I have similuar problem efi relay ticks when its not running if u put the key in it stops pull key out its starts ticking it starts fine run fine. Just when u pull key out it starts ticking what can i do

replying to Ray O, Byron pierce wrote: I have removed cover and even taken the relay out i checked it its ok but there seems to b some other problem i charged my battery its fine and no water anywhere i can tell im stumped