2008 Saturn Vue I’m helping a friend with. I know little about Saturn Vue but am handy enough working on various cars. Here are symptoms:

A) new battery

B) driver door
- key button and armrest button locks door
- key button and armrest button do NOT unlock
- no sound is made when try to unlock

C) three other doors
- lock and unlock perfectly

D) gas door
- key button and armrest button do NOT unlock
- someone jimmied it open, so does not fully close

E) rear liftgate
- does not lock and unlock
- currently not possible to open
- no sound when try to lock or unlock

Accessed Chilton wiring diagram. Learned door lock fuses and relays are in “Fuse Block - I/P”. Driver door lock and gas door lock share same fuse and relay, and fuse is OK, so seems relay is bad. Three other doors are on separate circuit. Liftgate also has separate circuit.

There is a very convenient fuse block to left of front passenger, but no door relay there, so wasted time looking elsewhere. Finally figured out, from previous post on this forum and from looking at wiring diagram more carefully (says LOCK PCB Relay), that the relay is probably on the printed circuit board, CANNOT be separately pulled and replaced.

My questions:

1) Any chance another fuse block containing a door relay? (I guess NO)

2) Do I need to replace the circuit board? (I guess YES)

3) Where might I buy replacement circuit board?

4) Any other comments or suggestions?

Thanks, Daniel

 

The underhood junction box has relays and fuses for the vehicle as well. The inside of the cover of the box will give you the layout. Same as the IP junction block. Go by those not the Chilton book for fuse ID.

You said the three different other doors were on another circuit. Did you mean all three are on a single circuit or each of the other three are on their own individual circuits? I suppose if they have zero added features as compared with the driver door, they could all share one circuit.

Does the schematic indicate if that other circuit also uses a PCB based relay?

I can't see them putting that type of PCB on the other side of the firewall, so it's probably somewhere mounted below the bottom of the dash trim. I'm thinking likely near the back of the IP fuse panel but that is just a guess.

Can you post a picture of the circuit layout from the book?

Also need to know the particulars of your Vue engine, XE, XR, FWD, AWD???

It's possible some of the other circuitry on that board may control other functions like the tailgate lock, gas door lock. A picture of the schematic which includes the actual PCB and the inputs and outputs would be quite helpful

 

Thanks.

>> The underhood junction box has relays and fuses…

I also looked at the underhood junction box. It did not have any kind of door relay. Yes, I also looked at the inside of the I/P fuse block cover box as you suggested.

>> Can you post a picture of the circuit layout from the book?

* I am posting circuit layout for I/P fuse block from the chilton book.

* Also posting a picture of the physical I/P fuse block from the internet. Looks the same as the one in the vehicle. Two relays can be pulled out / replaced. Neither relay is for the doors, according to inside of the cover of the box.

* Also posting picture of back side of the I/P fuse block from the internet. Cannot see a printed circuit board. Perhaps hidden inside. Seems about 20 wires would have to be disconnected from back of old part, connected to new part.

>> A picture of the schematic which includes the actual PCB and the inputs and outputs would be quite helpful

All I have is the posted circuit diagram. Do not have more detailed PCB schematic.

>> Did you mean all three are on a single circuit?

Yes, there are four door relays, with the three other doors on a single circuit:

DOOR LOCK PCB Relay - Locks four doors and fuel door. Seems OK because all doors lock perfectly.

LOCK PCB Relay - Unlocks driver door and fuel door. Seems BAD because they do not unlock. Driver door locks perfectly, has to be manually unlocked. Fuel door does not function, stays locked all the time. 15A F/DR LCK Fuse is OK. Either silly they called it a “LOCK Relay” when it unlocks or I’ve got things mixed up.

DOOR UNLOCK PCB Relay - Unlocks three other doors on a single circuit. Seems OK because the three doors unlock fine.

RLYS PCB Relay - For liftgate. Not sure whether locks / unlocks / both. Seems BAD because liftgate does not lock or unlock. Just stays locked all the time.

>> Does the schematic indicate if that other circuit also uses a PCB based relay?

It seems all four relays use a PCB-based relay, based on the circuit diagram and the physical fuse block only having two relays that can be pulled, and neither one for doors. My guess is the door relays are part of a PCB inside the I/P fuse block.

>> I'm thinking (PCB) likely near the back of the IP fuse panel

All I see is the IP fuse panel (to the left of passenger). My guess is the PCB is part of the fuse panel, because all the wires coming out of back of fuse panel. Did not try removing IP fuse panel.

>> Also need to know the particulars of your Vue engine, XE, XR, FWD, AWD?

Do not have that information.

Thanks again, Daniel

Back of IP fuse block (screenshot from internet)

Front of IP fuse block (screenshot from internet)

Circuit diagram for door locks from chilton book

 

I have the same door lock issues for 2008 saturn vue. how was the door lock problem resolved ? does the BCM need to be replaced ?

 

I'm sorry the problem is not resolved yet. It's a friend's car. She has had some mechanics take a look and she has not decided what to do yet. I wanted to replace the I/P fuse panel to the left of the passenger seat, because the chilton wiring diagrams show the door lock relays are on the printed circuit board. Fuse panel has not been replaced yet.

 

Sorry, I didn't mean to let this one drop and hit the floor. I will read it in its entirety tomorrow and see what else I can contribute.

 

I will be interested in learning whether replacement of the fuse block will solve the problem. it's hard to think that the PCB board is embedded inside of the fuse block molding.

 

Apologies. Strike two against me.

Check the gray wires at the bottom. That looks like a splice pack for all the grounds for the different relay circuits. The two that don't work are the two towards the center of the schematic. In addition to having that relay in common and the fuse in common, they also have that ground splice pack in common. It's not clear where the actual splice pack leads, but there is a slim possibility both of those ground connections are no longer connected. No ground equals no current. Given that the wire colors are included, as are what appear to be position numbers on the back of the fuse panel, you can try to track down the tan wires that you see in the pictures of the IP fuse panel back and see if you can measure voltage before the relay versus a good ground, not those ground wires initially. You want to verify that you have a current source. Then with someone actuating the switch, see if that voltage drops when they are holding the switch in or actuating it. If it does not change, then either that PCB relay is bad or the tan wire or this place pack ground has become ungrounded. The rest of this slice pack seems okay since the functionality is there. The above should tell you whether you have a complete circuit, as you are measuring the potential difference between what's coming into the relay with respect to ground ground a good ground. Then once you figure out which of the tan wires is the appropriate lead to ground of the splice pack, you can see if that is intact