Blinking switches lights: I see a big $$$$ problem here

[550Maranello]

This morning, while parking, lights were off, I stepped on the brake pedal and all switches' lights [AC, windows, defroster, etc.], all of them, started blinking at a rate of approximately 3 times per second. I lifted my foot of the brake pedal and they stopped blinking. I pressed the brake pedal again and they blinked again. Turned off the engine, restarted it and again all lights on and off. I left the car and came to my office.

Same thing happened about a month ago but since the problem went away and it couldn't be duplicated we forgot about it. My friend William thought it could be the cluster but the cluster lights never blinked.

I have the feeling that it is going to be costly to fix.

Any ideas?

Thanks much in advance.

Orazio

 

[gerryvz]

Was it a regular blinking pattern or just a random on and off?

Sounds to me like some sort of a ground or electrical contact issue. Have you checked the condition of your battery terminals, and of the grounding points behind the instrument cluster, behind the A/C switches and underneath the center console wood?

Also, have you checked condition of your fuses -- rotated all of the fuses in their sockets (particularly the one that controls the lights in question)?

I don't think it's an expensive issue. You just need to trace it to the point where the electrical anomaly is located. My experience is that 90% of the issues with electrical things going haywire are battery, ground point or fuse issues.

Cheers,
Gerry

 

[550Maranello]

Hi Gerry,

Thanks for your reply.

It was a regular blinking pattern and only with the brake pedal pressed on.

Per your recommendation I'll check battery terminals and check/rotate the fuses this afternoon. I will leave the task to check the grounding points to my friend.

Kind regards,

Orazio

 

[gerryvz]

You say same thing happened a month ago. Grounding related issues are often intermittent like that, and often seem very random in terms of what goes haywire with the car's systems.

What's weird to me with regard to this is the seeming connection between the brake lights/switch and the console lights. That's why I'm thinking it could be a common ground point because as far as I know, these systems are totally separate except at certain points like grounding points, the battery, or perhaps fuse terminals.

Cheers,
Gerry

 

[550Maranello]

Thanks again, Gerry.

I just checked the battery terminals and fuses but did not find anything wrong. Like you said, I'll check the grounding.

Nevertheless, I just have discovered that it happens all the time when braking, but I couldn't notice it with the lights on or at daylight.

I wonder how long have I been driving the car with this grounding problem.

Cheers,

Orazio

 

[gerryvz]

It's probably worth a check of the wiring diagram to see if and where there are any common electrical points or relays that intersect with the systems.

A copy of the wiring diagrams is attached to this message.

Cheers,
Gerry

 

[J. M. van Swaay]

Does the blinking correlate to the fasten seat belt light in the overhead module right by the rearview mirror? Reason I ask is that this module when faulted has been known to cause strange blinking light problems. Might be worth disconnecting to see if the fault goes away. (A very long shot but you never know.........)

J. M. van Swaay

 

[DerFuror]

Although this is an older thread, here’s some info that may help members…

This morning, while parking, lights were off, I stepped on the brake pedal and all switches' lights [AC, windows, defroster, etc.], all of them, started blinking at a rate of approximately 3 times per second. I lifted my foot of the brake pedal and they stopped blinking. I pressed the brake pedal again and they blinked again. Turned off the engine, restarted it and again all lights on and off. I left the car and came to my office.

Same thing happened about a month ago but since the problem went away and it couldn't be duplicated we forgot about it. My friend William thought it could be the cluster but the cluster lights never blinked.

I have the feeling that it is going to be costly to fix.

Any ideas?

The problem appears triggered by actuating the brake light switch. In this situation start by investigating the ground wire bundle mounting point condition in the trunk near the tail lights. Wiggle the wiring, check for looseness, corrosion. If no change, next check for a faulty brake light switch (it’s always good to have a backup switch on the shelf anyway). Swap a new switch in. Does problem go away? Hopefully one of these two actions will cure the symptom.

Does the blinking correlate to the fasten seat belt light in the overhead module right by the rearview mirror? Reason I ask is that this module when faulted has been known to cause strange blinking light problems. Might be worth disconnecting to see if the fault goes away. (A very long shot but you never know.........)

I was re-reading thru my car’s service documentation (PO’s ownership era). Here are some electrical problems & their solutions:

PROBLEM: DOME LIGHT STAYS ON AFTER OPENING & CLOSING THE DRIVER’S DOOR. ALSO, SEAT BELT WARNING IN THE DOME LIGHT ASSEMBLY FLASHES ALL THE TIME.

Solution: Defective Dome Light Assembly. Replace.

PROBLEM: BULB WARNING LIGHT COMES ON & (Head?) LIGHTS ARE WACKY.

Solution: Traced problems to defective head light switch & connector at right headlight (Note: this explains the old, but recently discovered, heat-related damage to my headlight connector. The PO “upgraded” to 9004 high-watt bulbs in 2008 & subsequently had to go back in to install more robust wiring to one of the two headlights. If experiencing a similar problem, do you have non-modified headlight connector harnesses supplying high-watt bulbs? I'm assuming the bulb connectors started to meltdown because the wiring gauge was not robust enough for the 100/80W application & the headlight switch sacrificed itself to save the rest of the circuitry).

Access & replace head light switch & solder in new connector harness for right head light assembly.