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I specifically need an answer to this question. How do I "backprobe J3D03 (Circuit 633, brn/wht wire) at PCM with voltmeter." according to 98-T-49A

I am troubleshooting a problem with my car running poorly. I **intermittently** get a Random Misfire code, and a P0340 (Camshaft Position Sensor) code. I have been told to read 98-T-49A. Part of the troubleshoting process says "backprobe J3D03 (Circuit 633, brn/wht wire) at PCM with voltmeter." How do I find these wires at the PCM? I know it's the black/white wire at the EI module. I also am wondering if I can just remove the connector at the ECM and test it, because I could not backprobe it while the connector was still on. I am at this step because I have tested the sparkplug wires/plugs, tested the EI module, and replaced the Ignition coils. It's an intermittent problem meaning it runs good sometimes, and bad sometimes. I've tried driving hot, and cold, and doesn't seem to matter. It must be a wire, but I can't get any information as to what parts could work intermittently. Surely it must be a short.

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  • 11 more comments 
  • Casey Van
    Casey Van May 16, 2015

    It's a 98 Saturn SL2. Why would it be the crank sensor when there is no code for crank sensor? The image that you posted would not load. I'll keep trying.

  • Jeff Armer May 17, 2015

    • An open or high resistance on the #1 plug wire or plug will result in DTC P0340 setting.

    • Inspect the EIS towers and plug the wire connections for corrosion or other signs of poor retention at connections.
    Important: A cam pulse missing may not affect engine operation.

  • Jeff Armer May 17, 2015

    You have a random misfire this is causing a false cam sensor code , check your plug wires an plugs !

  • Casey Van
    Casey Van May 18, 2015

    I've checked resistance across the plugs through the new ignition coils, and spark plug wires for 1 and 4, and 3 and 2, and they are within specs. Spark plugs were replaced less than a year ago, and I don't see significant deposits. I replaced plug #1. But seriously I'm 100 percent sure that checking plugs, and plug wires is barking up the wrong tree, because the issue is intermittent. If the plugs/wires were bad, it should be a constant problem not on and off. I'm looking for an intermittent problem like a wire, or overheated EI module, or PCM. That's why I'm asking a specific question. I've done all the troubleshooting, and replaced ignition coils, but I can't get to the next step, because I don't have a PCM pinout diagram, or at least I didn't when I wrote this question. I am still looking at diagrams.

  • Jeff Armer May 19, 2015

    I have it ,if you have an email address ! I can't down load on this site for some reason ,do you need a wiring diagram also . There is one more thing you can try ,if you haven't already .Ford in there troubleshooting test's call it the wiggle test , take the wiring harness an shake it wiggle it a round an see if you can make it act-up ! find general spot in the wiring harness that mite be suspect !

  • Jeff Armer May 19, 2015

    I can't believe what I'm reading here in my service info , are you sure you didn't replace a crank sensor an not a cam sensor ?
    COMPRESSION SENSE IGNITION: Both the SOHC and DOHC engines utilize Compression Sense Ignition, which eliminates the need for a camshaft position sensor. The EI module has sensing circuitry that detects when cylinder #4 has fired on its compression stroke and relays this information to the PCM. The PCM can then correctly synchronize the fuel injectors for sequential fuel injection. The EI module uses capacitive pickup plates located under the 1/4 coil to determine when cylinder #4 has fired on compression. These plates are used to differentiate the polarity and voltage amplitude difference between the 1/4 secondary ignition circuits. Since each coil tower is of opposite polarity and the waste spark (2-4 kV) generally fires before the compression spark (10-25 kV), the module can determine cylinder #4 compression. When the EI module detects a positive to negative polarity sequence and a high negative voltage spike, it will pull the PCM 5-volt cam signal circuit to ground. The PCM knows that cylinder #4 had just fired on its compression stroke when this transition occurs.

  • Jeff Armer May 19, 2015

    never mind I read your first post an see you haven't replaced a cam sensor !

  • Jeff Armer May 19, 2015

    D3
    BRN/WHT
    633
    .35
    CYL #4 SIGNAL
    Pink PCM connector third wire from the right on the top an right below it an open spot ! on the right side BLK/WHT wire ! on the left an open spot !

  • Jeff Armer May 19, 2015

    pull ,wiggle the wires at the EI module to check for terminal tightness ! you could have a lose connection somewhere !

  • Casey Van
    Casey Van May 19, 2015

    Good idea on jiggling wires, I will try that, because I'm thinking it's that connector that went bad. My motor mounts are bad, and that might have caused the problem, or the radiator leak, or oil, it's mess, needs lots of work.
    I tried cleaning the connector with a toothbrush wetted with orange cleaner, and blow some air on it. I used some radiator sealant that had bits of copper/aluminum etc. in it.
    I could not find any labels for the connectors under the dash when I looked there. I tried to take pictures but they came out blurry. I'll try to look again. I mainly am trying to locate where underneath there is the connector that I'm looking for. I think I didn't know what labels to look for, so I didn't look for the C, and D labels. I think it's labled A,B,C, and D so once I find those labels, I can guess the location of the wire, and confirm it by the color of the wire. I'm thinking it's a wire somewhere, either the ICM connector, or the cranskhaft position sensor.

  • Casey Van
    Casey Van May 19, 2015

    I don't see any labels, but maybe it's out of focus.

  • Casey Van
    Casey Van May 20, 2015

    So it's the pink one in the upper right? That's the only one with 32 pins that's pink. I could narrow it down by tracing the wiring harnesses.

  • Jeff Armer May 20, 2015

    You say on your post up top the wire is BLK/WHT at the EI module it's not is the same brown an White wire as at PCM ! The black/white goes to the under hood junction box > Pin D at the EI module is the one you want .

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  • Cars & Trucks Master
  • 15,575 Answers

You need a pin out chart of the PCM connectors an a wiring diagram ! You need T pins to back probe the terminals . What make ,model an year vehicle . This just an example of a connector pin out chart ! What Saturn do you have ? It sounds more like a crank sensor then a cam sensor ,whit the way it's running ! I mite be able to help , I have Saturn service info an all GM 1996 to 2009

Labscope cam sensor test

Posted on May 16, 2015

  • 9 more comments 
  • Jeff Armer May 17, 2015

    They don't always set codes

  • Casey Van
    Casey Van May 18, 2015

    Good to know, thanks.

  • Jeff Armer May 19, 2015

    Oh no don't use orange cleaner, go to the parts store an get electrical connector cleaner! Is that the PCM ? there should be a pink connector, that's the one you want !http://www.zoro.com/crc-contact-cleaner-...

  • Jeff Armer May 19, 2015

    CRC 05103 Quick Dry Electronic Cleaner - 11 Wt Oz.

  • Casey Van
    Casey Van May 20, 2015

    I'm not cleaning the actual contact point, just the wires that lead up to the contacts. I tried jiggling the wire while the car was running and I got mixed results. The car almost stalled when I pressed down on the wires gently but firmly with a stick, then recovered, but I could not replicate the problem.

  • Casey Van
    Casey Van May 20, 2015

    Also I noticed that when I steer the car left or right the car idle speed changes when idling at a stop.

  • Jeff Armer May 20, 2015

    Idle changed because there is a power steering pressure switch , It tells the PCM there is a load on the system so the PCM raises the idle! Glad to hear you not using that orange stuff on the terminals ! Did you try waggling the wire terminals at the ignition module ? an the connectors at the PCM ?

  • Jeff Armer May 20, 2015

    Yes the upper right , pink ! you could run a jumper wire in place of the original an see if it still has the problem !

  • Casey Van
    Casey Van May 20, 2015

    The idle lowered, not raised. So the load on the system is what caused it to idle lower.

  • Jeff Armer May 20, 2015


    Power Steering Pressure Switch


    The power steering pressure (PSP) switch (Figure 40) monitors the hydraulic pressure within the power steering system. The PSP switch is a normally closed switch that opens as the hydraulic pressure increases. The PCM uses the input signal from the PSP switch to compensate for additional loads on the engine by adjusting the idle rpm and preventing engine stall during parking maneuvers. Also, the PSP switch signals the PCM to adjust transmission electronic pressure control (EPC) pressure during the increased engine load, for example during parking maneuvers.

  • Casey Van
    Casey Van May 20, 2015

    It'd doing the exact opposite. Wierd.

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Where can i get an 01 silhouette pcm pinout


PCM pinout diagrams
2001 silverado (Thanks Banker099)

Try this link for page below


wol_error.gifThis image has been resized. Click this bar to view the full image. The original image is sized 799x247 and weights 17KB.connectorc1pcm2001.gif

Powertrain Control Module (PCM) C1 (BLU)



Connector Part Information
• PCM Connector C1 Assembly 12191489

• TPA (BLU) 12176408

• Connector Cover 12191108

Pin
Wire Color
Circuit No.
Function

1
BLK/WHT
451
Ground

2
LT GRN
1867
12 Volt Reference

3
PNK/BLK
1746
Fuel Injector 3 Control

4
LT GRN/BLK
1745
Fuel Injector 2 Control

5-10
--
--
Not Used

11
LT BLU
1876
Knock Sensor 2 Signal

12
DK BLU/WHT
1869
CKP Sensor Signal

13
ORN/BLK
463
Requested Torque Signal

14
ORN/BLK
1061
UART Serial Data [Secondary]

15
DRK BLU/WHT
774
UART Serial Data [Tertiary]

16
--
--
Not Used

17
DK BLU
1225
Transmission Fluid Pressure Switch Signal B

18
RED
1226
Transmission Fluid Pressure Switch Signal C

19
PNK
439
Ignition 1 Voltage

20
ORN
440
Battery Positive Voltage

21
YEL
1868
Low Reference

22
--
--
Not Used

23
PPL
719
Low Reference

24
--
--
Not Used

25
TAN
1671
HO2S Low Signal [- Bank 2 Sensor 1]

25
TAN
413
HO2S Low Reference (Denso Sensors) HO2S Low Signal (Delphi Sensors)

26
TAN
1667
HO2S Low Signal [- Bank 2 Sensor 2]

26
TAN
413
HO2S Low Reference (Denso Sensors) HO2S Low Signal (Delphi Sensors)

27
--
--
Not Used

28
TAN/WHT
1669
HO2S Low Signal [- Bank 1 Sensor 2]

28
TAN
413
HO2S Low Reference (Denso Sensors) HO2S Low Signal (Delphi Sensors)

29
TAN/WHT
1653
HO2S Low Signal [- Bank 1 Sensor 1]

29
TAN
413
HO2S Low Reference (Denso Sensors) HO2S Low Signal (Delphi Sensors)

30
LT GRN
1478
Coolant Level Switch Signal

31
--
--
Not Used

32
BLK/WHT
771
Transmission Range Switch Signal A

33
PPL
420
TCC Brake Switch Signal

34
WHT
776
Transmission Range Switch Signal P

35
GRA
48
CPP Switch Signal

36
BLK
1744
Injector 1 Control

37
YEL/BLK
846
Injector 6 Control

38
PNK/WHT
1101
Damping Lift/Dive Signal

39
--
--
Not Used

40
BLK/WHT
451
Ground

41
BLK
407
Low Reference

41
GRA
720
Low Reference (w/o Delphi HO2S)

42
--
--
Not Used

43
RED/BLK
877
Fuel Injector 7 Control

44
LT BLU/BLK
844
Fuel Injector 4 Control

45
GRA
474
5 Volt Reference (FTP Sensor)

46
GRY
474
5 Volt Reference (TPS Sensor)

47
GRY
597
5 Volt Reference (MAP Sensor)

48
GRA
596
5 Volt Reference (EGR Sensor)

49 50
--
--
Not Used

51
DK BLU
496
KS [1] Signal

52
--
--
Not Used

53
BLK
470
Low Reference

54
BLK
452
Low Reference

55
BRN
1456
EGR Valve Position Signal

56
--
--
Not Used

57
ORN
440
Battery Positive Voltage

58
DK GRN
1049
ECM/PCM/VCM Class 2 Serial Data

59
YEL
710
Class 2 Serial Data

60
ORN/BLK
469
Low Reference

61
PNK/BLK
632
Low Reference

62
--
--
Not Used

63
GRA
720
Low Reference

63
TAN
413
HO2S Low Reference (Denso Sensors) HO2S Low Signal (Delphi Sensors)

64
--
--
Not Used

65
PPL
1670
HO2S High Signal [- Bank 2 Sensor 2]

66
PPL
1666
HO2S High Signal [- Bank 2 Sensor 1]

67
--
--
Not Used

68
PPL/WHT
1668
HO2S High Signal [- Bank 1 Sensor 2]

69
PPL/WHT
1665
HO2S High Signal [- Bank 1 Sensor 1]

70
BRN
1174
Oil Level Switch Signal

71
--
--
Not Used

72
YEL
772
Transmission Range Switch Signal B

73
BRN/WHT
633
CMP Sensor Signal

74
YEL
410
ECT Sensor Signal

75
PNK
1020
Off/Run/Crank Voltage

76
BLK/WHT
845
Fuel Injector 5 Control

77
DK BLU/WHT
878
Fuel Injector 8 Control

78
--
--
Not Used

79
WHT
687
3-2 Shift Solenoid Valve Control

80
ORN/BLK
510
Low Reference
wol_error.gifThis image has been resized. Click this bar to view the full image. The original image is sized 799x247 and weights 17KB.connectorc2pcm2001.gif

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2008 ford explorer stereo wiring diagram


The audio control module (ACM) has a pair of stereo in inputs. The right channel is BLU/GRN + and WHT/GRN -; the left chaanel is YEL/GRN + and BLU -.

LF speaker: WHT + and WHT/BRN -; RF speaker: WHT/VIO + and WHT/ORG -; LR speaker: WHT/GRN + and BRN/YEL -; RR speaker: BRN/WHT + and BRN/BLU -

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Not finding FAS wirin on diagram.


Here ya go, maybe this will help.

6_3_2012_2_33_22_am.gif

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I have a 2001 l200 and it is giving error code p0340, and now wont start. Its does roll over though. How do i repair this issue


Most of this came from TSB 98-T-49A, and a few of my tips thrown in.

Both P0340 and P0341 both relate to the Camshaft Position Sensor(I will just call it Cam sensor from now on), the only problem is that the S-Series engines don't have a Cam sensor, not a typical one at least. instead, the DIS module watches when the #4 spark plug fires on the compression cycle and fakes a Cam sensor signal from it. the tricky part is that on a DIS waste spark system, spark plugs fire with their mated cylinders(1/4 and 2/3 in 4 cylinder engines) every time the cylinder is at TDC, regardless of weather the cylinder is on exhaust or compression. However, it takes far more voltage to fire a spark plug on the compression stroke then on the exhaust stroke, due to the compressed air(more air molacules, more air the spark needs to jump, more resistance to spark). The increased voltage needed on the compression stroke is detected by the "#4 sensing circuit" inside the DIS module for the Cam sensor signal. if the resistance of the secondary system is not in the proper range or something else is affecting the voltage draw, the "#4 sensing circuit" will be unable to work properly.

In short, anything worng with the ignition system, bad Cam sensor signal.

Next for the diagnositic, i'm converting this from a graphic map to a text format, so bear with me...

Step 1: remove secondary wires from spark plugs, keep the wires on the coil. measure resistance from #1 wire to #4 wire and then #2 wire to #3 wire. resistance should be 11k ohms to 45k ohms(YIKES thats a wide range)

If resistance is in specs, go to step 2, if not in specs, go to step 3


Step 2: remove secondary wires from the coil packs. check for corrosion on the towers and wires.

If there is corrosion, go to step 4

If not, go to step 5


Step 3: remove secondary wires from the coil packs. check for corrosion on the towers and wires.

If there is corrosion, go to step 4

If not, go to step 6


Step 4: Replace or clean coils and/or wires as nessaciry. Retest to confirm.


Step 5: Remove spark plugs. Check for carbon or abnormal wear and proper gap(0.040 in)

If plugs check out good, go to step 8.

if the plugs are bad, replace as needed and retest to confirm.


Step 6: Measure resistance of individual secondary wires. specs are 1.5k ohms to 15k ohms ( thats what this chart says, but my knowage says 8k ohms is normal, greater then 12k ohms should be replaced)

If wires are in spec, go to step 7

If wires are bad, replace as needed and retest to confirm


Step 7: Measure resistance from tower to tower on the coil packs (hold tight for good reading). Spec is 8K to 15K.

If coils are in spec, go back up to step 5

If coils are bad, replace as needed and retest to confirm


Step 8:(90% of the time i bet the problem is solved by now) Start engine. Perform underhood visual inspection of the ignition system, check for arcing(best done in a dark area, if you are inside a garage, besure the exhaust is vented). Wet DIS module, coils, and secondary wires with salt water to provide optional ground path.(arcing from the wire boot to the valve cover is possible, but would be hidden)

If arcing is present, replace wires or coils as needed and retest to confirm.

If not, go to step 9.


Step 9: Turn ignition off, backprobe J3D03 (Circuit 633, brn/wht wire) at PCM with voltmeter. connect other lead to ground. Turn ignition on, engine off. Measure voltage.

less then 4.5 volts, go to step 10
4.5-5.5 volts, go to step 12
more then 5.5 volts, go to step 11


Step 10. Check connections in circult 633, repair short to ground, retest to confirm


Step 11. Repair short to voltage in circuit 633, retest to confirm.


Step 12. Start engine, at idle observe voltmeter

less then 2.0 volts, replace DIS module, retest to confirm
2.0 - 4.0 volts, problem intermittent
4.0 - 5.5 volts, go to step 13
more then 5.5 volts, go back up to step 11


Step 13. Turn ignition off, backprobe circuit 633 at DIS module with voltmeter, other lead to ground. check voltage.

4.0 volts or less, repair open/high resistance in circuit 633, retest to confirm.
greater then 4.0 volts, go to step 14


Step 14: Inspect terminal on DIS module for looseness or poor connection.

If terminal is bad, repair it
If terminal is good, replace the DIS module.



thats all of the diagnoistic chart, anybody who has done this in the past feel free to throw in your tips/opinons. I would like to add three things:

1. Check the grounding bolt on the DIS module for corrosion.
2. besure the secondary wires are fully seated, you should feel/hear a click
3. use dielectric grease on the coil towers

Dec 23, 2010 | Saturn L-Series Cars & Trucks

1 Answer

Stereo wiring for a 91 honda accord


1. red/blk ---------lighting switch
2.wht/yel-----------to fuse No.24 (7.5A) under hood relay box
3. yel/red---------- to fuse No. 11 (10A) Dash fuse box

4.brn/blk ----------- (--) R front speaker
red/grn ----------(+)

6. brn/blk-------------(--) L front
blu/grn

7.brn/wht -----------(--) R. Rear speaker
red/ywl-------------(+)

8. gry/wht----------(--) L..Rear
blu/yel ----------(+)

9.BLK----------------- to the ground.


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Need colour codes for stereo wiring for 2000 hyundai accent


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97 saturn sc1, #1 cylinder not firing, b4 new coil, whts next?


Vin "7" or '9"???if #4 is firing so is #1. they both fire at the same time. have you swapped the wire with number 4 or another cylinder? have you checked for a injector pulse on #1 fuel injector? Compression on #1 Cylinder?

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1 Answer

Stereo wiring diagram


(+)blu/yel and (-) gry/wht to LR
(+)red/yel and (-) brn/wht to RR
(+)blu/grn and (-) gry/blk to LF
(+)red/grn and (-) brn/blk to RF
if u want a pic let me know your email and i send it to you.

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1 Answer

Need help with 2004 Hyundai Santa Fe Audio Wiring


Sounds like you need a light tester. I would guess that at least 8 of the wires are speaker + & - the others will be Main power and earth Possibly electric ariel, Memory store and a wire for the anti theft circuit. Assuming the stereo is factory. Any Audio shop can perform a test to clarify the purpose of the wires Wouldnt worry about the blank its probably a position for a newer or different model to yours. Steve in the UK

May 13, 2009 | 2004 Hyundai Santa Fe

1 Answer

No fire to the plugs


Well let me give you a brief understanding of the electrical ignition system.

The PCM controls the ground circuit for the ignition coil ground circuit. So basically the PCM determines when to open and close the ground circuit for each individual ignition coil, therefore making it give power to the spark plug or not.

The ignition coils get there power from a power distribution center which as an ASD (Automatic Shut Down) Relay located inside of it. So your problem may lay within this.

Also, like you said, you may need to check the crankshaft and camshaft sensors because they give information to the PCM which then calculates the best timing for the system.

To check the crankshaft sensor first check the harness and test to see if the sensor is getting 5.0 volts. To do this you need to connect the positive end of a voltmeter to the orange wire terminal and the negative lead the the black/lt blue wire terminal at the harness connector. Then turn on the ignition and check the voltage. If voltage isn't right check the wiring between the PCM and the sensor.

If you are getting the correct voltage next check the sensor itself. You need to reconnect the harness to the sensor and you need an analog voltmeter. Then you need to backprobe the harness, which is sliding the probes from the meter into the wire side of the harness, if you meter has clips then get a sharp pin and slide into the harness and clip the meter to the pin.

Checking the Crankshaft Position Sensor

With the sensor connected, backprobe the gray/black wire terminal of the sensor connector to the positive lead on the analog meter and the negative lead connects to an engine ground. Turn the ignition key On and with a breaker bar and sockey manually turn the crankshaft clockwise. Do one full revolution and keep an eye on the meter, if you get readings of 5.0 volts then the sensor is good if not replace the sensor.

Checking the Camshaft Position Sensor

Again check the harness for the sensor first. The positive lead of an analog voltmeter connects to the orange wire terminal and the negative lead to the black/lt blue wire terminal. Turn ignition on and you should get approx. 5.0 volts. If voltage is incorrect check the wiring.

If wiring the harness is giving adequate power now check the sensor. Its the same idea used to check the crankshaft sensor but this time connect the power lead of the meter to the backprobe connected to the tan/yellow wire terminal and the ground lead to a good ground. Turn ignition On position and manual turn the crankshaft clockwise a full revolution while also checking for the meter to fluctuate between 0.0 and 5.0 volts. If you don't get the proper reading then the sensor is bad.

This should help solve your problem.

Apr 16, 2009 | 2004 Dodge Intrepid

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