[cajunrebel]

I have just finished the majority of a OBDII swap and a full engine rebuild. I had the bronco where it would run and drive (trans would not shift and no speedometer at all, turned out to be an overlooked ground). But I had a check engine light (I expected one) and went to download it and the tester would not connect. The tester had voltage at the OBDII port but would not connect to the computer. I thought there might be an overlooked plug in the dash, but when I removed it and researched I found out that the only plugs not installed are for the doors and the rear air bag sensor. Everything else in the truck is hooked up. Any thoughts? Does anyone have the schematic for the OBDII port to the ECCV computer that I can test the wiring?

 

[miesk5]

yo CJ,
I may have sent you this in our other discussions;
in attachmt below, image # connectorblue
Diagnostic Link Connector (DLC) Pin-Out Diagram in a 96
Pin 2 - J1850 Bus+
Pin 4 - Chassis Ground
Pin 5 - Signal Ground
Pin 6 - CAN High (J-2284)
Pin 7 - ISO 9141-2 K Line
Pin 10 - J1850 Bus
Pin 14 - CAN Low (J-2284)
Pin 15 - ISO 9141-2 L Line
Pin 16 - Battery Power

--------
J1850 Bus Positive/Data Positive & Negative/Data Negative (Return): MIESK5 NOTE, I think this is from/to Diagnostic Link Connector (DLC) (Test Connector) and then to PCM

===============

Connector Pin-Out Diagram with Circuit Functions in a 96 5.0 and 5.8 (Scroll Down) from 1996 F-150, 250, 350 (4x4), and Bronco Vehicles Workshop Manual

Pin Number Circuit Circuit Function
1 315 (P/O) PCM to Transmission Shift Solenoid No. 2
2 658 (P/LG) PCM to Check Engine Indicator Lamp
3 � Not Used
4 � Not Used
5 � Not Used
6 651 (BK/Y) Dedicated Ground
7 � Not Used
8 � Not Used
9 � Not Used
10 � Not Used
11 � Not Used
12 � Not Used
13 107 (P) PCM Flash EEPROM Power Supply
14 784 (LB/BK) 4x4 Low Range Switch to PCM Indicator Lamp
15 915 (PK/LB) J1850 Bus Negative/Data Negative (Return) to PCM
16 914 (T/O) J1850 Bus Positive/Data Positive
17 � Not Used
18 � Not Used
19 � Not Used
20 � Not Used
21 � Not Used
22 � Not Used
23 259 (O/R) Dedicated Ground to TFI Module
24 570 (BK/W) Dedicated Ground � PCM
25 875 (BK/LB) Ground Logic Module
26 � Not Used
27 237 (O/Y) PCM to Transmission Shift Solenoid No. 1
28 � Not Used
29 224 (T/W) Transmission Overdrive Cancel Switch to PCM
30 � Not Used
31 � Not Used
32 � Not Used
33 676 (PK/O) Vehicle Speed Sensor � Negative (Return) to PCM
34 � Not Used
35 392 (P/LG) Heated Exhaust Gas Oxygen Sensor No. 3 to PCM
36 968 (T/LB) Mass Airflow Return
37 923 (O/BK) Transmission Oil Temperature to PCM
38 354 (LG/R) Engine Coolant Temperature Sensor to PCM
39 743 (GY) Air Charge Temperature Sensor to PCM
40 238 (DG/Y) Fuel Pump Monitor to PCM/Fuel Pump Relay to Safety Switch
41 198 (DG/O) A/C Pressure Switch to Control Relay
42 � Not Used
43 � Not Used
44 200 (BR) PCM to Air Management No. 2 (Was TAD)
45 � Not Used
46 � Not Used
47 360 (BR/PK) PCM to Electronic Vacuum Regulator � Constant Current
48 382 (Y/BK) PCM to Test Connector No. 2
49 395 (GY/O) Profile Ignition Pickup to PCM
50 929 (PK) PCM to Spark Angle Pulse Width/Spark Output
51 570 (BK/W) Dedicated Ground � PCM
52 � Not Used
53 924 (BR/O) PCM to Transmission Coast Clutch Solenoid
54 480 (P/Y) PCM to Transmission Converter Clutch Control
55 37 (Y) Battery to Load
56 191 (LG/BK) PCM Top Vapor Management Valve � Constant Current
57 310 (Y/R) Knock Sensor No. 1 to PCM
58 679 (GY/BK) Vehicle Speed Sensor � Positive to PCM
59 917 (DG/LG) Misfire Detection Sensor � Feed
60 74 (GY/LB) Heated Exhaust Gas Oxygen Sensor No. 1 to PCM
61 � Not Used
62 � Not Used
63 � Not Used
64 199 (LB/Y) Manual Lever Position Sensor to PCM
65 352 (BR/LG) Delta Exhaust Pressure Transducer to PCM
66 � Not Used
67 � Not Used
68 � Not Used
69 � Not Used
70 190 (W/O) PCM to Air Management No. 1 (Was TAB)
71 361 (R) Power Output from PCM Relay
72 561 (T/R) PCM to Fuel Injector No. 7 Cylinder
73 559 (T/BK) PCM to Fuel Injector No. 5 Cylinder
74 557 (W) PCM to Fuel Injector No. 3 Cylinder
75 555 (T) PCM to Fuel Injector No. 1 Cylinder or Bank No. 1
76 570 (BK/W) Dedicated Ground � PCM
77 570 (BK/W) Dedicated Ground � PCM
78 � Not Used
79 911 (W/LG) PCM to Output Circuit Indicator Lamp/Overdrive Cancel Indicator
80 926 (LG/O) PCM to Fuel Pump Relay Control
81 925 (W/Y) PCM to Electronic Pressure Control No. 1
82 � Not Used
83 264 (W/LB) PCM to Idle Speed Control Motor No. 1
84 136 (DB/Y) Output Shaft Speed to PCM
85 � Not Used
86 � Not Used
87 94 (R/BK) Heated Exhaust Gas Oxygen Sensor No. 2 to PCM
88 967 (LB/R) Mass Air Flow Sensor to PCM
89 355 (GY/W) Throttle Position Sensor to PCM/Diesel Fuel Injector Pump Lever Sensor
90 351 (BR/W) Power to Engine Sensors
91 359 (GY/R) Sensor Signal Return
92 511 (LG) Stoplamp (Brake On/Off) Switch to Stoplamps
93 387 (R/W) HEGO Sensor Heater Voltage Monitor No. 1 to PCM
94 388 (Y/LB) HEGO Sensor Heater Voltage Monitor No. 2 to PCM
95 389 (W/BK) HEGO Sensor Heater Voltage Monitor No. 3 to PCM
96 � Not Used
97 361 (R) Power Output from PCM Relay
98 562 (LB) PCM to Fuel Injector No. 8 Cylinder
99 560 (LG/O) PCM to Fuel Injector No. 6 Cylinder
100 558 (BR/LB) PCM to Fuel Injector No. 4 Cylinder
101 556 (W) PCM to Fuel Injector No. 2 Cylinder or Bank No. 2
102 � Not Used
103 570 (BK/W) Dedicated Ground � PCM
104 � Not Used


96 MY OBD II Serial Data Link MIL IlluminationThe instrument cluster on some vehicles uses the J1850 serial data link to receive and display various types of information from the PCM. For example, the engine coolant temperature information displayed on the instrument cluster comes from the same ECT sensor used by the PCM for all its internal calculations.
These same vehicles use the J1850 serial data link to illuminate the MIL rather than a circuit, hard-wired to the PCM. The PCM periodically sends the instrument cluster a message that tells it to turn on the MIL, turn off the
MIL or blink the MIL. If the instrument cluster fails to receive a message within a 5-second timeout period, the instrument cluster itself illuminates the MIL. If communication is restored, the instrument cluster turns off the MIL
after 5 seconds. Due to its limited capabilities, the instrument cluster does not generate or store Diagnostic Trouble Codes.

 

[cajunrebel]

Thanks Miesk! Just what I needed once again. I will check the wiring when I get up later. Its cold and windy in the desert this time of night and I already spent all night out working on the jets.

 

[miesk5]

yo, YW buddy,

I hear ya (I think, I lost some hearing from that racket too...worse was balst bounce of da jet blast deflectors on CVNs

 

[cajunrebel]

I am down a fair bit hearing wise from my time out on the ramp as well. Eyes are still great though. Unfortunately I cant get a break to work on the bronco today either, a co-worker snapped a water pump bolt off in his timing cover and its his only ride, so off to the rescue!

 

[cajunrebel]

I just checked the wiring and the pin #2 on the OBDII port does not have continuity to pin #16 on the EEC. Guess I am gonna start tracing the wiring and see if there is a break. If I cannot find one I will piggy back a new wire in.

 

[miesk5]

yo, ok
On the EC, ck pin for what Ford describes as "pin or terminal back-out"... meaning the pin on female side may be askew, bent or seperated from its wire.
Almost there CR!

 

[cajunrebel]

I pulled the backshell from the EEC connector and the wire seemed tight and connected. My next step is going to be checking that wire for continuity from the EEC connector to the bulkhead connector at the firewall, and then from the firewall to the OBDII port. The entire run of that wire is only around 8 feet at most. If there is a break inside of a harness then I will solder in a piggyback wire. No reason to tear into the entire harness for one wire. The female terminal on the EEC connector also looked to be in good shape from external examination. I inspect connectors similar to that on a daily basis so I am a fair judge.

 

[cajunrebel]

Pulled the bulkhead connector loose at the firewall and the wiring has continuity from the EEC to the firewall, but none from the firewall to the OBDII port. I will piggyback a wire in tomorrow and see how it goes.

 

[cajunrebel]

So After messing with the wiring for a while I could not find a short with the system taken apart and attributed it to a bad connection when I first installed it. I put the dash back in and plugged everything back up. But I still cannot connect. I am going to try a different OBDII scanner before I do much else. I also went back and checked for continuity with everything connected and I have it. The J1850 bus is intact and I am not sure what it wrong now.

EDIT: I just went over to the bronco and checked the pins on the OBDII connector vs the pin out that miesk5 gave me. I have pins 2 and 10 the 1850 bus, pins 4 and 5 which are both ground, pin 16 which is keyed power, and then pin 13 which does not correlate to anything that I know of. Pin 13 does not show up on any schematics that I see online. WTF is pin 13!

 

[miesk5]

yo,
I messed-up when I C&P from the 96 EVTM; had a lag and over-wrote the pin id info; SORRY MAN!..

Here is the Diagram again

 

[cajunrebel]

Well that schematic is certainly what I see in my truck Miesk. But the thing that confuses me now is the fact that the code scanner I am using does not have a pin 13! If that connects to the PCM in some way to tell it to transfer codes then that could be my problem. Is the PCM wire just one that needs ground to start the communication process?
EDIT: after looking through Steve83's OBDII swap on his crown vic, it appears that OBDII pin #13 goes to PCM pin #13 (convenient). The PCM diagram has that listed as being 107 (P) PCM Flash EEPROM Power Supply. But I am not sure what it would be supplying power to. I will investigate this pin #13 a bit more.
Edit: looking around online using the model number of the scanner I am using (an Actron CP9180), I noticed that someone else was not able to get their E-350 7.5L to download. These vehicles both use very similar EECs which also likely communicate with the scanner in the same way. Its possible that this older format used by these EECs is just not compatable with the scanner. I will try another.

 

[miesk5]

yo,
All I can get now is from my site and the EEC V pin diagram I posted above;
PIN 13 107 (P) PCM Flash EEPROM Power Supply

 

[cajunrebel]

I talked to a buddy and he seems to believe that pin #13 is for programming the EECV. So no need for it on the scan tool. Now I just have to find a scanner that will connect.

 

[cajunrebel]

I got the scanner to connect and pull codes tonight. The OBDII buss is up and running. Was a corroded connection in the wiring at the bulkhead connector. Ended up with a TPS code. Have to adjust it and try again.

On a related issue, I was able to drive the truck, but the transmission would not shift. The speedometer works and seems steady so I think the VSS is good. Tone ring was in o shape when I pulled the diff cover a few weeks back. Would a bad TPS cause the transmission to not shift? There is also the MLPS, but I did not move it when I installed the transmission. I will try rerigging it and see it it improves tomorrow.

 

[cajunrebel]

I believe that the TPS did not get installed properly. I took it off and reinstalled it correctly and now I am getting voltage to the EEC harness. My idle is still high even with the IAC unplugged. With it plugged in it is about 1100 to 1500. Unplugged I am just under 1000. Still not getting shifts from the transmission and it feels like it is not giving good pump pressure. I will try the OBDII scanner again tonight when my buddy gets off work and see if the computer is reading TPS voltage. I had a bandk 2 O2 sensor that was not reading right but had not yet thrown a code. Threw in a new one and got the same results. May look into its wiring as well. Do both the TPS and the O2 sensors get their referance voltages from the same wire?

 

[miesk5]

yo,

I am having trouble opening more browsers to ck that VREF
EDIT; EEC V PIN 90 is VREF 5V reference
see this Diagnosis & Testing Course Training by Henry J, Page 4-18,
104 pin PCM Power and Grounds
Pin - Function Description
3 PWRGND Power ground
71 VPWR Voltage input to module
13 Flash EPROM Power Supply
76 PWRGND Power ground
15 Bus (-) Data Link Connector (DLC)
77 PWRGND Power ground
16 Bus (+) Data Link Connector (DLC)
90 VREF 5V reference
24 PWRGND Power ground
91 SIGRTN Signal return
25 CSEGND Case ground
97 VPWR Voltage input to module
51 PWRGND Power ground
103 PWRGND Power ground

Connector pinouts for the 104 pin PCM vary from vehicle to vehicle, but the power, ground, and data bus circuits have the same pin numbers throughout all vehicle lines (where 104 pin PCMs are used).
look @ Connector Pin-Out Diagram with Circuit Functions in a 96 5.0 and 5.8 I posted above

Throttle Position (TP) Sensor Test on page 113 verifies PIN 90 is VREF 5V reference
& Pin 91 359 (GY/R) is Sensor Signal Return


PIN #90 351 (BR/W) Power to Engine Sensors

O2 sensor wirng diagram in a 96 5.0

see pin #90? R/W wire, ckt 387

same for TPS, wiring diagram Brown/W to pin 90

 

[miesk5]

yo,
BTW, I think I mentioned in another thread that any malfunctioning sensor could (prob will) affect others.
I looked thru our discussions here and didn't see it; but I couldn't open all threads.

 

[cajunrebel]

I am reviving a bit of an old thread of mine. I am in Korea so for now all of this will sorta be discussing possible issues and not fixing them for now. When I installed my E4OD I noticed some transmission fluid in my solenoid pack connector. I used some CRC contact cleaner and then put dielectric grease in the connector before plugging it in. Could the grease have caused me to not have a proper connection? I thought that it would help stop corrosion and displace any possible transmission fluid in the future. But now I feel that it may have been a bad idea and have actually caused my shifting issues (or rather lack of shifting) that I am now facing.

 

[cajunrebel]

Bump. Still looking for insight about the grease in the connector.