Intermittent electrical: hazards, ER sp, cruise

[lovehate]

Mechanic and I are trying to track down a vexing problem - 2007 subaru outback turbo, manual transmission. Three main symptoms and I have good reason to believe they are related:

1. At first, the hazard lights would begin flashing intermittently while the car was on (usually while driving but also noticed while idling). They would flash 2 or 3x and then stop for a while, then flash again. This happened very intermittently and we could not track down the cause.

2. Then lately, I have had the cruise disable while driving and cruise light start to flash with no check-engine light (and mechanic verified no error code). If I turn the car off and back on, it clears - until it happens again, intermittently.

3. Now lately I have had the speedometer intermittently stop functioning and the er SP code display in the trip meter. Again, happens intermittently and not in a predictable or reproducible way. Sometimes it will even clear itself while I am driving.

The reason I think these three things are related is that I found this post:
Answer : SUBARU OUTBACK 3.0R 2005 ELECTRONIC PROBLEM
in which someone mentions the exact same set of three problems. Mine are also occurring typically in winter or early spring during wet slush/snow or heavy rain. Sadly, there was no solution posted to that discussion.

Does anyone have any thoughts about what could be causing all three. Is it a short somewhere that I am doomed to sink hundreds of dollars into chasing to maybe never find and have it crop back up again on a slushy day? Anyone else ever experience these three together. Thoughts?

Thanks all!!

[cardoc]

Check the battery amperage (not voltage) output and grounds. Battery needs to be putting out over 450 amps to effectively run the car and this is the low end. With a good battery the alternator needs to be checked flat and under load. Check ground conductance between the battery and alternator, battery and firewall, battery and block. No more than 50 amp loss is perfect. If its over 50, start cleaning grounds. Check the ground lugs on both sides of the interior at the kick panels. Check for corrosion on or in the cables.

[lovehate]

Definitely will check these things. The other piece of the puzzle that perplexes me is that these problems don't happen every time it rains or is slushy - but seem to happen after long consecutive days of driving in high moisture. I saw one post on a related symptom that implicated moisture in the interior cabin from wet feet (floor carpet getting soaked).

I am curious about the thoughts from the group as to whether the problem would more likely be interior to the cabin or in the exterior engine area. It would seem to me that since all three are instrument cluster related that there is a high possibility it could be a problem in the cabin.

Do these three systems share any other common elements/wiring that anyone can think of?

[plain OM]

It might be a stretch, but there is a possible connection between all three symptoms, and that's the body integrated unit. The BIU is the main "router" for the car's LAN, as well as having specific functions such as keyless entry/security.

The ErSP in the trip meter is referring to a communications problem (LAN) relating to vehicle speed. Without this data, it's very possible the speedometer will be problematic.

The flashing hazard lights is probably not the "hazard" warning per se. Nor is it the turn signals going crazy. Instead, consider that when the keyless entry is used to lock or unlock the car, the turn signal/hazard lights outside flash one or two times. It's the BIU that causes the lights to flash when the fob is used. If there's a problem with the BIU (or something related to it,such as LAN communications), the BIU might be causing the turn signal lights to flash intermittently.

And, without reliable vehicle speed data, the cruise control would be disabled intentionally.

[kcatchword1]

Originally Posted by lovehate

Mechanic and I are trying to track down a vexing problem - 2007 subaru outback turbo, manual transmission. Three main symptoms and I have good reason to believe they are related:

1. At first, the hazard lights would begin flashing intermittently while the car was on (usually while driving but also noticed while idling). They would flash 2 or 3x and then stop for a while, then flash again. This happened very intermittently and we could not track down the cause.

2. Then lately, I have had the cruise disable while driving and cruise light start to flash with no check-engine light (and mechanic verified no error code). If I turn the car off and back on, it clears - until it happens again, intermittently.

3. Now lately I have had the speedometer intermittently stop functioning and the er SP code display in the trip meter. Again, happens intermittently and not in a predictable or reproducible way. Sometimes it will even clear itself while I am driving.

The reason I think these three things are related is that I found this post:
Answer : SUBARU OUTBACK 3.0R 2005 ELECTRONIC PROBLEM
in which someone mentions the exact same set of three problems. Mine are also occurring typically in winter or early spring during wet slush/snow or heavy rain. Sadly, there was no solution posted to that discussion.

Does anyone have any thoughts about what could be causing all three. Is it a short somewhere that I am doomed to sink hundreds of dollars into chasing to maybe never find and have it crop back up again on a slushy day? Anyone else ever experience these three together. Thoughts?

Thanks all!!

Someone who owns a subaru say s that subaru uses a vegetable based solution on the insulation of the wiring and the mice love it check your car for mice hopes that helps

[tdelker]

We had a similar issue. Car was under warranty. Turned out a mice ate some wires under the rear seats. Not sure exactly where as the dealer fixed them.