Look on the 1988 R/V series wiring diagram page 43 PDF page 285... The plug in question is in the lower centre of the page.
PDF pages 289 & 290 have the ECM circuit number assignments and wire colors.
GM circuit #s Circuits follow
- 419 Brown/White ECM A-5 Inst Cluster #15 Malfunction Indicator Lamp
- 434 Orange/Black ECM B-10 Park Neutral Switch
- 437 Brown VSS to ECM A-10
- 450 Black Engine Ground to ALDL, ECM, ...
- 451 White/Black ECM A-9, ALDL B. Diag Enable
- 461 Orange ECM A-8, ALDL E. ECM Serial data
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1959 M35A2 LDT465-1D SOLD
1967 Dodge W200 B383, NP420/NP201 SOLD
1969 Dodge Polara 500 B383, A833 SOLD
1972 Ford F250 FE390, NP435/NP205 SOLD
1976 Chevy K20, 6.5L, NV4500/NP208 SOLD
1986 M1008 CUCV SOLD
2000 GMC C2500, TD6.5L, NV4500
2005 Chevy Silverado LS 2500HD 6.0L 4L80E/NP263
2009 Impala SS LS4 V8
RTFM... GM Parts Books, GM Schematics, GM service manuals, and GM training materials...
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