Harnesses, fuses and relays - Saab 9-5

[SaabWorld]

Information from the WIS for the 2005 Saab 9-5



Wiring harnesses

Saab 9-5 has eight wiring harnesses: front, power train, dashboard, front door, rear door, roof, tailgate and rear.

They connect all the electrical components in the car to their intended points of connection. Some components have their own harnesses for distributing power in the component. The electrically adjustable seat is one such example.

Main fuse boxes

All electrical distribution units are part of a wiring harness. The distribution units contain all the car's fuses and relays, with the exception of the relay in the passenger seat which allows operation without the ignition being on.

The engine bay contains:

• maxi-fuse box 501
• main fuse box in engine bay 342a
• main relay board in engine bay 342b

The main fuse box 342a and main relay board 342b in the engine bay are built in to one unit. The distribution units in the dashboard are divided into two separate units:

• main fuse box 22a
• main relay board 22b

Power supply for the car is divided into:

• Battery supply
• +30-supply
• Power supply (+15 circuit)
• Power supply (+54 circuit)
• +X-supply
• +B-supply

Battery supply

In addition to being supplied to the maxi fuse box 501, the battery voltage is also supplied directly to the starter motor, generator, both lighting relays as well as a number of fuses in the engine compartment main fuse box and fuse A in the dashboard main fuse box, see

These leads are unfused and great care must be exercised when measuring the voltage in these circuits.

The charging system is described in service category “Charging Systems” .

+30-supply

When the ignition is in the LOCK position and the key is removed, certain fuses and components are still supplied with power. The power supply comes first via one of the maxi fuses and a certain protection exists against short-circuiting. Great care is also recommended when measuring voltage before the fuses in the dashboard main fuse box and ignition switch, stalk switch, ignition switch relay, main relay for engine management system and start relay, see .

+15-voltage

When the ignition key is turned to the ON or START position, power is supplied from connector

pin 15 to a number of fuses in the dashboard main fuse box, see .

The voltage remains even when the key is turned to the START position.

+54-voltage

In the ON position, voltage is supplied from connector pin 54 to some fuses in the main fuse box in the dashboard as well as the relay coil at ignition relay 21. The relay closes and voltage is supplied via its connector to fuses both in the engine compartment and dashboard fuse boxes, see

When the ignition key is turned to the START position, the current is cut. This is to disconnect a large number of consumers during the start procedure so that the starter motor and engine management system will receive the highest possible voltage and ensure engine start.

+X-voltage

When the ignition key is turned to OFF from LOCK, voltage is fed from the X-pin to the light
switch, see .

The power supply is interrupted when the key is turned to the LOCK position.

+B-voltage

When the ignition key has been turned to OFF from LOCK, voltage is fed from pin B to fuse 5 in the dashboard main fuse board, see

The power supply is only interrupted when the key is removed from the ignition.

Fuse box 501 for maxi-fuses in the engine bay



Fuse box 342a in the engine bay



Relay box 342b in the engine bay





Fuse box 22a in instrument panel




Relay box 22b in dashboard

[Khamees79]

Hi. Thanks for the info. After the mechanic fixed a broken window (driver door), the two buttons for opening the baggage lock and for opening the fuel door are not working anymore.
He checked and they are connected to the wires. He thought it might be fuses that needs to be changed.
My question, in the list above, which fuse do I need to change?
And which type of fuses needs to be used (if there are multiple)?

sorry, it's my first car, and a newbie here. so Answers for Dummies are appreciated

[Burnsside42]

Likely he didn't reconnect the switches back up. Take it back and ask him to remove the panel and check this. Watch and see! Also - if that is the problem he should not charge you as it was his mistake.

[Khamees79]

Hi.

About the plugs in the door, we checked and they are connected, beside they are kind of fail-proof with color and type of plug, so I guess the fuse needs to be checked, just if I know which one it is.

[rodp]

Hi All,


Did anyone else fall into the trap thinking that the fuse box layout was different on their Saab 9-5 2007 MY06 but in actual fact you need to use the mirror image of what is in the car manual as it's showing the layout for a Left Hand Drive rather than a Right Hand Drive ?!?!? I did - spent ages trying to figure it out!! Oh well I can at least not worry about that anymore and I'll concentrate on replacing my fuel pump. That's another story mind you but I'm so glad that it didn't go on the way to the hospital with wife in labour in the back!!!! Happy to say Baby Theo was born weighing in 10lb11oz (ouch!), all doing well (now!!)


Cheers


Rodp

[J Frank Parnell]

[FONT=verdana]After trying to locate Fuse 35 to disable my daytime running lights, I decided to make a diagram that was a little more descriptive than the one in the manual. The confusion usually comes, since many of the open slots are loaded with spare fuses, which makes it hard to discern which fuse is what. I also noted two fuses that were 7.5 Amp in the manual, but came from the factory with 10 Amp in the slot (See the magenta blocks in my diagram). 16B was also filled with a 7.5 Amp fuse, and 19 was empty. This was not indicated in my manual. I think the fuse panel diagram has been the same for a couple of years, so it may work with your model year as well. Let me know if you have any corrections. JFP[/FONT]

[FONT=verdana]See the fuse panel diagram here: https://docs.google.com/viewer?a=v&p...thkey=CJ27_pwG[/FONT]