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Help! 1992 C4 code issues, its wearing me out...HELP

joe nissan

Member
Joined
May 9, 2013
Messages
5
Location
new york
1992 C4 CONV. 80,000 miles.

SYMPTOMS:

Service ASR light on, speedometer reads ZERO, security light flashes every 15 seconds 3 times, runs well, starts every time, but wont rev above 3000 RPM.

Codes: jumped pins a and g.

Module 1- c41, h41, h53, h54, h72,h74

Module 4 error

Module 9 h64, h72

I tried the following> replaced Ecm, looked at all the grounds, still cannot cummunicate with ECM


HELP....
:happyanim::mad
 
Welcome onto the boards there...

Do you have FSM?

Any one of the codes that you have could defer to another code. Bad ECM grounds can cause all kinds of problems.

Why did you replace the other ECM? Do you still have it? You should get it back... 'Looking' at grounds really won't tell too much -
 
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Module 1- c41, h41, still cannot cummunicate with ECM
C41 active.

Loss of Communications
The Serial Data Circuit is a master (CCM)/slave (ECM) configuration.

The CCM polls the ECM. If the ECM fails to respond after 3 consecutive polls (3x200ms/600 milliseconds) a Code 41 sets.

The Serial Data Circuit links Serial Data 1 to Serial Data 2, which includes the electronic HVAC controller, ECM, ALDL terminal, and anti-lock braking controller.

Check wiring/connections between the CCM and ECM and the ground (G106 LH rear of ENG, near oil filter/RH bellhousing for VIN J; G109 RH middle ENG compartment, on frame; G401
Vert: Cargo compartment, behind RH seat, Coupe: RH side of halo, near top RH seat).

There's a splice that connects all of these devices which is the central point of the physical layer path. This splice is located behind the Cruise control module on the Instrument panel harness.
All the devices that connect to this serial Data link circuit all use the same color TAN wire.triple check these links for shorts to ground and Battery and open circuits.
Keep in mind:
A short will take down the entire Serial data circuit, thus affecting communication between all devices.
A single open circuit will take down just that specific device.

So think of these links as a Hub and spoke. The splice is the hub and all the devices via TAN wire connect to this splice are the spokes.

Diagnosis:
Jump ALDL TERM "G" and "A"
IGN ON
Press "TRIP RESET" until "4.0" displays in Trip Monitor
Note Speedo, does it say "ERR"?

NO
A SHORT will take down the whole link. An OPEN will take down only the device(s) that becomes OPEN circuited.

Possible inop TRIP controller.
Loss of English/Metric TEMP display on C68 HVAC control head.
Loss of "Check Gauges" function.

YES
IGN OFF
DIS red (VIN8) or blue (VINJ/LT5) ECM connector
DIS white CCM CON
CON Digital Volt Meter (DVM) between CCM TERM WC13 (800 TAN) and ECM CON TERM R11/B15 (VIN8/J)
Continuity?

NO
Repair OPEN in CKT 800 to CCM PIN WC13

YES
CON DVM between CCM TERM WD12 (800 TAN) and ECM CON TERM R11/B15 (VIN8/J)
Continuity?
NO
Repair OPEN in CKT 800 to CCM PIN WD12

YES
CON Digital Volt Meter (DVM) between CCM TERM WC13 (800 TAN) and GND.
Continuity?

YES
Repair SHORT to GND in CKT 800

NO
CON TEST LIGHT between CCM TERM WC13 (800 TAN) and GND.
IGN ON
Test Light ON?

YES
Repair SHORT to B+ in CKT 800

NO
Repeat test from first "YES", except use use ECM TERM R5 where R11, and B20 where B15, is specified.
 
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