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Old 04-08-2010, 03:49 PM
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Join Date: Apr 2009
Location: Seattle Area
Posts: 108
Default Fuel Pump Inoperative

The rear IGN 1 relay should be installed and working correctly when you try to read the trouble codes.

If the relay or control circuitry to the relay are not working, just jump power thru the rear IGN 1 fuse and try reading the codes again. Make sure you jump power thru the fuse. The jump will activate the instrument panel cluster. You can test that the power is available by activating the turn signal with the ignition on.

If this test works it points again to the rear IGN 1 relay control side wiring or to components in that wiring like connectors or the ignition switch.
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Old 04-08-2010, 10:07 PM
Join Date: Oct 2009
Posts: 33
Default Trouble Codes

I finally got the trouble codes to pull up with the engine running and all circuits normal.
ABS C1246, C1284, C1285, C1287
No AMP codes
DDM B3832, B3833
DIM B1983
IPC B1004, U1040, U1088, U1000
NO IPM codes
IRC U1000, U1160, U1016
PCM P02030, P0449, P0650
NO RFA codes
RIM B1327, U1160, U1255
SDM B0066
NO VTD codes

Hooked up a scan tool got:
P0650, P0449
Freeze Frames read;
Fuel sys 1 OL-DRIVE
Fuel sys 2 - OL DRIVE
Calc load 4.71
ECT (C) 20
STFT B1 (%) 0.00
LTFT B1 -0.78
STFT B2 0.00
LTFT B2 0.00
MAP (KPA) 38.00
Eng RPM 946
Spark ADV 13.00 Vehicle speed 9
IAT(C) 22
MAF (G/S) 11.96
TPS(%) 1.18
Air Status UPS

Hope this helps...I cleared ALL CODES afterwards.
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Old 04-09-2010, 02:24 PM
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Join Date: Apr 2009
Location: Seattle Area
Posts: 108

It is likely that many of the codes you have could be caused by removing the solenoid to start the car along with a bad ground or wiring connection. They are also consistent with the possibility of a bad ground, bad wiring connections, bad wiring, or a bad ignition. Check the grounds, the wiring to and from the solenoids, and the ignition key as previously described. Operate the two front windows. Then clear the codes to eliminate any codes caused by troubleshooting.

Next drive the car twice up to 50 or 60 mph for a few minutes shutting the car off between each time. Now read the codes again. It will also be helpful if you identify which codes are current verses those that are listed as history.

C1246 is not related to your problem. The brake pad wear sensor read greater than 2.93 volts most likely because the ground has been broken. Check your brake pads and all four sensors for wear and replace the defective sensor. The sensor is just a bit of wire that wears thru when the brake pads are too thin.

B3832 and B3833 are also not related to your problem. The codes mean your express up operation was not set before clearing the codes. They show up every time you disconnect the battery to work on your car or disconnect power from the module. To keep them off your list you have to follow the following procedure after you reconnect power. Operate each of the front electric windows all the way down, then all of the way up. This procedure sets the express up operation. Next clear all codes.

P0449 is not related to your problem. It is on the circuit controlled by the rear IGN 1 relay and is setting when you pull the relay and drive. Many of the other codes on your list are related to your problem, but are probably caused by your starting procedure or bad wiring. If you still have the fuel pump problem after troubleshooting the wiring, post the new code list.
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Old 04-09-2010, 02:34 PM
Join Date: Oct 2009
Posts: 33
Question Fuel Pump/Electrical problem T/S

Removing 1st the underhood IGN1 & ACCY relays and using an ohmmeter I came up with the following readings. Understand without a wiring diagram I will show the slots of the relay & post the readings from each point. Using engine block as a grnd source.

Front BEC

#38 IGN 1 relay
___74.5 ohms ___
___ ___ 00.7 ohms

ACCY relay
___00.7 ___
___ ___

ohmeter set @ 200 ohms

Rear BEC

#41 IGN 1 relay
___ ___

___0.00 ___

#39 Fuel Pump Relay
___ ___

___0.00 ___

With IGN switch ON @ each relay voltage readings

Front BEC

#38 IGN 1 relay
___11V ___.5V

___12V ___

___ ___

___12V ___12V

Rear BEC

#41 IGN1 relay
___12V ___11.75V

___ ___5.70V

#39 Fuel pump relay
___12V ___12V

___ ___1.5V

I also have the following code ID #'s
ABS 2230
AMP 7436
DDM 7410
IPC 2456
IPM 3026
IRC 0806
RFA 5964
ROM 2584
VTD 3641

I'm heading to library to get a wiring print for the BEC's & FUEL SYS. Let me know what ya come up with. Those high OHM readings on IGN 1 relay (front BEC)?

Last edited by fabes; 04-09-2010 at 02:47 PM.
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Old 04-09-2010, 05:09 PM
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Join Date: Apr 2009
Location: Seattle Area
Posts: 108

If I understand your chart, look for a short to voltage in the ground or a bad ground to the rear IGN 1 relay. The 5.7 volt reading shown at the control side ground should be near zero. If the ground is bad, voltage could be backfeeding from the control side ground of other relays in the rear fuse block, from the heated seat modules, or from the remote door lock receiver. The common ground is G301.

You should not get voltage at the control side of the fuel pump relay when the front IGN 1 relay is also removed.

You should be able to get conductivity readings at both ground side terminals of each relay. Ignore the 74.5 ohm reading because that is taken at a voltage supply terminal.
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Old 04-09-2010, 09:14 PM
Join Date: Oct 2009
Posts: 33
Default Fuel Pump & MIL

I found the Engine Controls Schematics at the library which breaksdown the Fuel pump & relay. I see the distribution of the G301 ground, can you tell me how it is routed? Where's the connection point for each end as far as location on the chassis? What does 1 BLK 750 mean? Also where's the G401 located?

Not that familiar with auto electrical schematics, legends are different. Plus still getting familiar with data software.

Thanks for all the help so far....feel like I'm getting closer.
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Old 04-10-2010, 11:21 AM
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Join Date: Oct 2007
Location: in the mitten
Posts: 2,681

I have been following this thread for while. It seems electical concerns have been for a while. Is car stock(that includes stereo) or "modded"? Did you get it this way or it just happened? If it just happened, any repairs or alterations done prior? Sunroof? In "flood zone"? These questions haven't been asked.
It will be OK
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Old 04-11-2010, 12:13 AM
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Join Date: Apr 2009
Location: Seattle Area
Posts: 108

To answer your questions:

G301 is under the left passenger seat near the rear fuse block. I am pretty sure that you were looking at the ground distribution schematics (G301), sketch number 642474, in the manual. The routing is from position D2 in rear fuse block C1 and position D10 in rear fuse block C2 to the G301 ground connector. The body and accessories section of the manual has a sketch #679991 showing the location of the ground and also has sketches of the rear fuse block connectors.

A voltage drop check across the ground with the ignition on can verify the effectiveness of the ground. There is instruction in the manual on how to measure voltage drop, but you already did it when you found the 5.7 volt drop. My theory is that the G301 is bad and power flowing thru one of the other devices that shares that ground has found an alternate ground thru G104 by way of the ignition. See the Power Distribution Schematic for (Ignition Switch) and ELC, INJR 1, and INGR 2 Fuses), sketch numbers 642412 and 642437, for the possible routing.

You performed a voltage drop check when you found the 5.7 volt reading at the IGN 1 relay control side ground connection, contact L3. You can pinpoint the location by performing the voltage drop check at other locations in this circuit. Because there are parallel grounds from the rear fuse block to G301, I don’t think the problem is at the fuse block connector or the 16 gauge black wires. I suggest first trying a voltage drop check across the G301 ground.

'1 BLK 750' describes the wire. In this case the wire is 1.0 mm or 16 gauge thick, the insulation is black, and the wire is a component of circuit number 750. The electrical schematics are scattered thru out the manual so circuits and connections are shown on multiple pages. There is an electrical schematic location list under body and accessories - wiring systems that is of some use.

G401 located is in the right side of the trunk. See sketch 154461. I don't think this is your problem because you didn't mention that the problem was related to the tail lights and you already found a poor connection in circuit 750.
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Old 04-13-2010, 04:33 PM
Join Date: Oct 2009
Posts: 33
Default Electrical checks REAR FUSE BLOCK

I just took 20 minutes to write a lengthy explanation of my findings and when I hit submit it kicked me off...Oh well!

Here's a shorter version....G301 connector reads 134.4 ohms. I isolated to only reading 134.4 ohms with the bottom of rear fuse block center junction connected. D2/D10 read 0 ohms wire terminal to wire terminal only when disconnected from bottom of rear fuse block. The other 3 ground wires at G301 are reading 0 ohms.

When the bottom of rear fuse block center junction wires are connected, the tabs at D2/D10 read 134.4 ohms. With it disconnected and fuse block on its own, meaning nothing is connected to it, D2/D10 read 0 ohms.

I read each wire terminal at the center juntion and came up with the following: E2-70 ohms, A1-1.5 ohms, B4-14 ohms, D9- 1.8 ohms, A9- 38 ohms, B12-2.3 ohms, E12-1.9 ohms.

Where does each pin go? I do not currently have a diagram for that junction until I make it to library. Grounds should read 0 ohms, why does this one read 134.4 ohms with center juntion connected to rear fuse block?

The G301 Connector that mounts with a bolt to the body of the rear floor is where I started. The readings where 134.4 ohms with it connected/disconnected from the rear floor. When I isolated the wires/terminals, that's when I came up with the high readings on D2/D10 grounds, while the other 3 grounds came up 0 ohms.


Last edited by fabes; 04-13-2010 at 07:08 PM.
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Old 04-13-2010, 09:40 PM
Join Date: Oct 2009
Posts: 33

I found diagram for rear fuse blocks and C2 was the one I was referring to earlier. Pin E2 shows circuit 2 ignition positive voltage (70 ohms), pin A1 Park brake relay A supply voltage (1.5 ohms), pin B4 park brake relay B+ supply voltage (14 ohms), pin D9 fuel door release solenoid (1.8 ohms), pin A9 trunk release motor (38 ohms), pin B12 interior lamp control (2.4 ohms), pin E12 courtesy lamp supply voltage(1.9 ohms).

Why does rear fuse block pin D2 @ C1 connector have 134.4. ohms along with pin D10 @ connector C3 ? Like I asked earlier, since they are grounds, why are they showing high resistance only when C2 connector is mounted to block?
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